A piece of Interfit Magic

Now, look. I know that these pictures are, shall we say, a little on the heath Robinson side. OK, I'll admit it, they're crap, but at 6:00 am and people in bed, I'm not about to start ramping up the K20. Also, my mobile phone is flat. These are taken with the rather not-so-trusty point and shoot.

Also, my trusty mesuring tape has gone AWOL so I had to use a seamstress tape for the measurements, so give my figures a little leaway here.

What I'm introducing you to is the Interfit COR754 Combi Boom stand. At just shy of £80 they aren't cheap, either. However, they are a little bit of magic, and by the end of this post, you'll know why.

Seen here against a trusty COR750, the 754 is larger and has a curious assembley at the top. It isn't light, either, coming in at 1.6kg (3.5lbs).


With legs splayed in this manner, it stands 46 inches (just under 4 foot) and will fully extend to 86 inches high (just over 7 foot) To the knuckle, it will stand 6' 8" high, and this will become clear at the end of the post. Like all the other stands, it has a standard thread at the top to take brackets and accessories.

This is the lower section showing the upward extension. As you can see there are two parts to it, but the lower of the two is quite short; the upper part of this extension is what is responsible for most of the vertical height.

This is the knuckle. Part of the magic is that when you extract the centre pole all the way up, it allows the knuckle to swing. This will allow the pole to not only go horizontal, but actually downwards back towards the floor if you need it.


The "horizontal" pole, for want of a better destription, comes backwards and allows you to hook through some form of weight to counter balance whatever you put on the pole, and as this pole extends from its normal 39" to 71", that is a fair distance on which you can put something.


And this is the last bit of the witches brew. Two wide bulldog clips which, when the horizontal arm is fully extended, will go apart to about 63" - that's five and a quarter feet. Man ... I tell you ... this thing can take a piece of cloth over 5' wide and hold it up at 6'8" in the air. Instant background with any cloth you desire.


Trust me; I've been doing battle with enough background cloths over the last year or so, to know when something is going to give me a big boost. Getting a second one of these for the other side will enable backgrounds to go much further apart for family portraits and the like, as these things seem to be solid. The only issue in putting these up in a home is the wider leg splay.

However, if you mimick the bulldog clip on a standard light stand, then while this can hold an 8' background at one side and in the centre, a standard light stand could then take up the far end. There are possibilities here and I'll report on them in due course.

There was one thing that I did do, which was to disconnect the central knuckle so that I could reverse one of the bulldog clips so that they were both on the same side of the pole. That was straightforward.

The ultimate question for most people, however, is how much weight can this thing take. Well, for those of you that know your Interfit kit, the Stellar X 300 isn't on the light side, but here it is on the boom. With the extension arm retracted to the max, plus a counterweight, plus only using the lower vertical extension section, also having the extension boom arm positioned directly over one of the splayed legs, then yes, it is possible to put a mains strobe plus softbox up in the ceiling.


The breaking weight doesn't seem to be listed, and you certainly don't want to be doing this sort of trick without a counter ballance weight. You'll also notice that the extension arm is bending very slightly, (some of the bend in the image is optical illusion due to the ceiling) so while getting a mains strobe head aloft is certainly possible and very doable, I wouldn't use this to do it with any regularlity.

It does prove, however, that battery strobes, soft boxes, brackets, etc., etc., etc., can be easily hauled aloft with great confidence.

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Lies, damn lies and ...

"Statistics show that 433,900 compact cameras were sold in May 2009 - that's 73,400 fewer than in May 2008." according to Amateur Photographer. Given that the UK population in 2007 was measured at about 61,000,000 by government statistics then it is possible interpolate that every person would have had a camera in roughly 120 months, that's 10 years.

If you took a family of 4, then every family would have a decent, modern compact camera in 2.5 years. That sounds realistic for me. The technological boom for compact cameras reached a peak in terms of megapixels about three or four years ago. Cameras of that age would no doubt be delivering all the quality needed for most families, leaving the sales to only cover those that were dropped in the pool by Uncle Jack, lost forever on the Heathrow carouselle, met an untimely fate of baby food thanks to an unthinking toddler or otherwise crunched by the family pet. (if said pet was a goldfish then those cameras unfortunate enough to meet Uncle Jack might have suffered a double fate of drowned and chewed ... or at least drowned and sucked.)

But at this point, technology might have met its match anyway, recession or not. Take Blu-Ray for example. Sales have never overtaken DVDs and don't show the likelyhood of ever doing so before the next format emerges; price is one factor in this but the other factor is quality. Households seem to be happy with DVD and BluRay offers no significant benefit for the price. People aren't abandoning DVD for Blu Ray in the same way that VHS was abandoned for DVD.

The same can be said of cameras. We are now way beyond the 1 megapixel quality of the earliest cameras of a decade ago. Point and shoot cameras are delivering quality way beyond the average family needs; so why upgrade?

Heck, the cameras coming fitted on some mobile phones as standard are enough for many people, so the point and shoot gets squeezed at the bottom end ... not through technical capability, as the P&S will always be more advanced than the camera phone ... but through requirement.

Throw this in to the mix and who knows what the hell is going on. Are these new sales professionals or serious hobbyists trading up to new cameras while the manufacturers cut back on holding stock? I mean, take the short report... "Digital camera production plummeted 28.9% in the first five months of 2009, according to figures released by Japanese manufacturers. Though the total number of digital SLRs made dropped 21.4%, compared to the same period the previous year, DSLR production was only down 3% on the same month in 2008. And DSLR shipments to Europe were 2.3% higher in May 2009 than in May 2008, state the figures released by the Camera & Imaging Products Association (CIPA)." Sales go up a little, yet production goes down dramatically on a yearly basis but on a month by year basis it only goes down a little. I mean ... how on earth are we supposed to get to grips with these numbers?

Probably the most important question on many photographers lips is whether this will impact on the masses of people now trying to sell their pictures.

It isn't easy to find out how many users are on Red Bubble, but using the New Users page roughly 250 people sign up every day. For a service going for two years, that comes to about 200,000 people worldwide selling their wares there. I'll admit, not all of them are photographers. With a world population of about 6.77 billion, (American billion, not a British billion) that is ... one in every 33,850 people are selling their wares on Red Bubble ... that's about 0.003% - and that's just the people who are using Red Bubble - you can bet that the number of people selling their pictures was significantly smaller before digital was invented.

So how do we measure the number of competitors in the field? A good camera can last years, so we can't do it by camera sales. Pictures sold only measures demand, not supply. When someone in the world hangs up their camera there is no record of the fact. We can, however, be certain that digital has opened the door to artists as well as photographers; the magic of a photographer has always been a mix of technical skill and artistic vision and better technology has opened the door for those who have artistic vision but weaker technical skills, to realistically enter the competative market.

Statistically, the numbers just aren't there to find out how many people we are up against.

The music industry had record sales; that was torn to shreds by digital. Writers still have a section of formal publishers who weed out the amateurs and their sales statistics still count for something, but DRM on reading devices threatens to throw them in to the same mire as the music industry when it inevitably gets hacked. Photographers have recently seen the collapse of the traditional sales systems and are in the process of an image sales rebirth. Not even seasoned industry pros can forecast where all this is heading.

The only advice that I am picking up, is to keep the head down, stay local and stick with the personal touch. If the world wants to know you, statistically, it will come to your door when it wants to.

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Just spotted...

I've just spotted ... geddit ... spotted! ... these background cloths at what seem to be reasonable prices. Being free of a stand system they seem cheaper and becuase they haven't got a stand that means they could be a good degree more flexible. They are currently at Morris Photo and if Radio Popper haven't got the UK JrX system running by this time next month, I might get one or two, probably Stormy Blue and Sahara ... but that's just my own personal taste.

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Comparison - part 3

Well, you can see the results for yourself. The camera was fixed at ISO 100 and tungsten balanced. The bronze statue was put in a soft box with the standard 45 degree lighting generated by tungsten desk lamps. The camera was on a tripod and triggered by remote control. The pictures were shot in RAW. There were no filters on the front of the lenses. The camera was used in aperture priority.

I took a series of shots, but these were taken at f8 on both lenses and basically tell the whole story. Measuring from the models head to the first lens element, the closest the 200 could get and still focus was 90cm. For the 135 this was 80cm. Both lenses were set to 135mm as best as I could manage.

It doesn't take any guessing to work out which lens is responsible for which picture. These pictures are both recorded at Jpeg quality 6 out of photoshop and even that can't muddy the stark difference between these shots. I tried whatever I could to improve the 200, including adjusting the focus range up and down ... it made no difference to the results. The 135 is so damn sharp I could prick myself.






I have concluded that the lens is definately worth the money. The £530 I paid for it, yes, but the £920 it has risen to, no.

It is going to cause me a fair bit of grief as I now have to re-work my storage and carrying methods. Quality certainly comes at a price. More pictures with this lens as I take them.

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Comparison - part 2

Before getting to the optical testing, the practicalities of having a lens like this have to be taken in to consideration.

As well as the increase in weight, there is also an increase in size. This brings its own problems.


I store lenses in one of two ways...

Technique number 1 is my most favoured. The hood is left on the lens at all times. This negates having to use a front element cap. It means that the lens is ready for action and switching between lenses takes seconds.

Technique number 2 is that for storage, the hood has to be reversed and the lens cap has to be applied to protect the front element. I don't like this for a number of reasons.

Reason number 1 is that it vastly increases the time to change lenses. If I am on a lazy shooting day, then it isn't that much of an issue, but if I'm really working to capture moments then the extra time and handling in mounting different front element caps and reversing the lens hood really does screw up the work flow.

Reason number 2 is that the very act of putting on and taking off the front element cap is a risk of damaging the front element coatings. If a risk like this is avoidable, then I'd rather avoid it. This risk also forces the wise to fit a permanent ND/UV/Skylight filter to the lens to help minimise any damage.

This brings us, however, to lens storage and the usual bags.

The separate lens bags that attach to the various strapping systems seem to be designed to handle these types of lenses very well. It is things like the day bags and the rucksacks that are having problems. You can see in the picture above that even with the lens hood in the storage position, the fixed section of the lens is protruding.

Provided that this lens proves its worth, I am going to have a good deal of soul searching to do about how I carry this lens and use it.

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Comparison - part 1

To get the bare statistics out of the way, the 50-135 is 18 elements in 14 groups while the 50-200 is 11 elements in 10 groups. In terms of weight, (with hood) the 135 weighs in at 765g, while the 200 comes in at 285g. That's coming on for three times the weight in the lens.

One of the first questions on my mind was how much was I going to lose with the 135 as opposed to the 200. Well, here is a comparison shot. The picture is taken with the 135 and the centre section is the area that the 200 captured.


That is a fair difference in my book. To make up for this, the 135 would have to be a better performer and make up for it in other ways ... which was what I was looking for it to do.

To get a better perspective on the range, here is a 50mm shot showing the brighter square being 135mm and the darker inner area being 200mm. On balance, for portrait work, which is what I intend primarily using this lens for, I'm not loosing that much. In terms of a general purpose lens, however, as this is also to take over from the 50-200 as the most used lens on the camera, that extra bit of loss will cause me some framing issues.


... issues that I suffered with the very first evening of my using the 135 when a hot air baloon sailed over my friends house and off in to the distance; I ended up with wires and tree tops in shot. Call me a nut case ... call me whatever you will ... but I find that the extra bit of focal length gets me out of so many situations and gives me a perfect crop so many times; I now have visions of having to manually crop many more images, just like I had to do with this one...

...and if I had used the 200 I'd have got a perfect crop, in camera, the moment I hit the shutter. For general photography, this is going to increase my post processing work and also lose me resolution in my end pictures which is a pain as the starter poster size for Red Bubble is 14 megapixels ... if I have to crop an image it means I can't sell it at poster size ... which is a serious bummer.

The second question on my mind was how close could I get to a subject. The 135 gets closest at 1m while the 200 is 1.1m. Although the 135 might appear to have the edge, this is cancelled out by the extra focal length of the 200 and then the difference isn't that much to write home about.

In terms of mechanical performance, there is a fair difference. The 135 is quieter, is weatherproof and feels more positive in its focusing. It is also performing well in terms of light at relative f stops, allowing a very slight increase in shutter speed of about a stop. These are improvements, definately, but certainly not enough to justify the price differential.

The weight is a negative. This lens, coupled with the K20 body and populated grip, takes the whole camera to 5lb, or 2kg ... that's a fair weight for a camera and is on the heavy side of hand held.

That leaves optical performance ... sharpness. This, however, was going to require a more controled test. I don't have any of those complicated test page thingamies, so flowers and models would have to do.

I won't show the shots of the flowers as 1:1 as the tripod wasn't stable, I haven't got used to the lens yet, but initial tests show that in less than ideal circumstances the degree of blur is no improvement over the 50-200. The real performance test is going to be under flash light and also stable tripod conditions.

So, what we have got so far...

• The move down from 200mm to 135mm won't matter too much for portraiture but will matter for general photography. I'll have to look for another lens to replace this and then keep the 135 for portraiture.


• The weight is a significant increase for prolonged hand held photography.


• The ultrasonic motor is much quieter and feels more positive in action.


• The weatherproof properties of the lens are reassuring, even though for £100 I used the 50-200 in the rain anyway.


• The slight increase in light performance is welcome but isn't earth shattering.

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It's here - 50-135 f2.8

Well, it's here. The Pentax DA* 50-135 f2.8 to be used in replacement of the 50-200 f4-f5.something ... you see, I've forgotten it already.


Using the lens is gorgeous. The ultrasonic motor inside does the focussing and it is ultra-quiet compared to the body focussing motor. Speed of focussing feels quicker, but possibly this is down to the lack of hunting ... which it only seems to do when I forget to take the lens cap off!!! In terms of focussing speed and ability, the sensing is done by the camera so I expect the lens to still perform badly in poor light, which is one of the known issues with the K20d. (but solved with the K7)

The other thing about Pentax is that they don't mess around; they STILL include a method of manual focus and also give a reading of focal point distance, so that focussing can be done manually according to a desired distance rather than requiring an object to focus on; something I do every now and then.


It is a smooth operator, indeed. Weather proof so I don't have to worry about shower damage. The manual focus ring doesn't move when the camera auto focusses which also means that when I change my focal length, I don't alter the focus. The lens mirraculously stays at f2.8 throughout the range. Sweet! The only noisy thing about the system now, is the shutter noise, which being a fully mechanical shutter, has always been a bit loud. (again, an issue solved with the K7)

The other thing about this lens is that the length of the lens does not change with the focal length. It just stays the one length.

I'll be out walking in the country next week, so I'll get a chance to test the 50-135 against the 50-200. There is no doubt that I've captured some wonderful images with the 50-200 and I am going to miss having that top end 200mm; remembering that I upgraded the 50-200 because it is my most often used lens, so it will be worth finding out if this will be worth the sacrifice in terms of image quality.

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