First Images with Adapter

I've had a preliminary and brief go at a few lenses, just to start testing the waters, so to speak. All ISO200 and on a firm tripod. Photoshop processing as per my standard approach has been identical in all cases.

The 35mm f/2.4 has no aperture ring, so was at minmum aperture. As might be expented, a poor result:


The 43mm f/1'9 Limited at f/4 looks much better:


The 100mm f/2.8 Macro at f/4 did not shine quite as much at this distance:


The Tokina 80-400mm at 200mm and f/16 was a bit of a star, but had to be on a different subject due to lack of close enough focusing:


The Tokina 80-400mm again at f/16 but now at 400mm wavered all over the place, so brighter light and shorter shutter speeds would be good, but pretty good anyway:


Conclusion so far is that good images may well be possible, but outdoors with higher shutter speeds will be needed to get a little more practice. Focusing is actually easy enough, but very precise indeed, so care is definitely needed!

Just to add to that, the 35-mm equivalent values would be:
35mm = 192.5mm
43mm = 236.5mm
100mm = 550mm
200mm = 1100mm
400mm = 2200mm

I take it these were using a K to Q adaptor John?

The 100 doesn't look too bad, the subject would have some influence over the sharpness, f5.6 od 8 may have given better results.

As for the Tokina at 400, a tripod looks like the 'must have' to use effectively.

All in, an interesting experiment.

Yes, these were K lenses on the Q. It was the simple £40 adapter, not being able to afford the Pentax one yet. The Pentax one has extra functionality so it will be the target if the simple adapter proves that using such lenses will be viable and useful.

I'll be doing much more testing in the new year, but for the moment just dipping a toe in the water....

Thanks John, my adapter should arrive soon so I will also post some test results.
Dave

All the time this type of post is making me think about a Q as a second camera...

...must..

...resist...

The problem with the cheap adapters is the sensor is active for 1/7th of a second, so the last pixel will always be 1/7th of a second after the first which pretty much rules out hand holding.

It works like this.

You set the shutter speed, let's say 1/100th of a second. The camera tells the sensor to record (turns the output on) and sets the scan rate of the sensor to 1/100th of a second so every pixel is active for 1/100th of a second, but they remain active for the whole time it takes the sensor to scan all the pixels (1/7th of a second), so the last pixels to be output have been 'updating' every 1/100th of a second so the data they output is lagging by 1/7th of a second from the first pixels if you see what I mean.

The slightest amount of camera and/or subject movement will be recorded looking at a slightly different part of the scene in the pixels recorded last compared to those recorded first, the result is a slight blur or softness and 'jello shutter'.

As the lenses on a Pentax Q we use with adapters tend to be either telephoto or macro exacerbates the problem because in both cases any camera shake is magnified, using an Infra Red remote whilst on a tripod will make a visible difference to pressing the shutter release on the camera, it's that sensitive to camera/subject movement.

The shutter mechanism in the Pentax Q - K adapter means all the pixels 'see' the same 1/100th of a second, as thereafter they just see black the pixels are not updated as it's below their threshold, so all the pixels record the same 1/100th of a second which solves the problem, but (currently) at a too high a price for me too John.

I hope you can follow what I'm trying to say here. And also my understanding is correct.

It will have to do for now Chris, but if static subjects work well, then the answer is clear...and expensive.

Got my adapter today, going to play with my DA*300mm tomorrow and see what I can do with it...

Only used my 3rd party adaptor a couple of times. Haven't produced anything that I would normally consider good enough to share. But for the purposes of this thread, here you go.

Q with 3rd party adaptor and Sigma 105 macro, at a very unobtrusive working distance. Shutter speed was only 1/160 at 400 ISO in natural light. Taken in September.

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Got mine today as well Neil! Rubbish with a quick test handheld with my 50mm f1.7, probably for the above reasons. Like you will try with my 300DA* tomorrow.
Dave

I know we've asked this before but can someone remind me if you put in the actual focal length in for the SR when requested or the 35mm equivalent. I noticed it caters for some ridiculously high values which made me wonder if it was the latter.
Dave

Conditions were not ideal and a trouble finding subjects when the sun was out (one I found was kindly scared of by a dog as I framed it!). In the end I ahd to settle for a blue tit as the sun went in.

Using Pentax Q and DA*300mm + unofficial adapter.

Taken at ISO 800 on a tripod 1/800th


blue tit by Neil Phillips, on Flickr

100%(ish) crop


blue tit 100% by Neil Phillips, on Flickr

It's not bad Neil. What distance were you? I think when I test I will do a 300mm on K30 with a crop to same size to see if it's worth the effort. How did you get on with locating and focusing? I'm thinking the use might be distant fairly static waders or distant rarities for record shots.

I was somewhere between 5-8m I would guess. I'm think waders with some decent sun behind me might come out well. Didn't find focusing and tracking too hard, easier than I feared. I managed to get a marsh harrier earlier nearly full frame but blurred due to motion. First time it flew over those reedbed in front of the hide in 4 years and I didn't have the k-5 on the lens!