[NoRules]

I just received a Pentax K and a Leica R to Q No-Name adapters for my Q7. Very low contrast and sharpness in all lenses I tested, even stopped down a bit. Well, sharpness improved, but still much lower contrast than I am used to. I then looked at the adapters. The exit holes are way to big for the tiny sensor. I installed baffles, two in each adapter, with a hole slightly bigger than the sensor, you know, like in a true telescope lens à la Leica Telyt or Novoflex Noflexar. Sharpness and contrast is now the way I like it. Lost 1&1/2 EV, but that was light destroying the image, not contributing to it. Stopped down, all lenses are razor sharp now. Favorites are Pentax 50mm 1.4, Leica R 60mm Elmarit Macro, Leica R 90mm Summicron and Leica R 180mm Elmarit. I expect to receive Pentax 100mm macro, 135mm 2.5 and 200mm 4.0 in just a few days, as I have ordered an adapter with shutter. Planning on doing some astrophotography soon. I'm just curious if anyone here is familiar with baffling the adapters? They are very poorly constructed regarding the cameras they are meant for. It took me half an hour and a sheet of black paper to get them right. I have searched the forum for a post regarding the issue, but could not find one. Sorry if this has been debated before.

Cheers!

[vonBaloney]

I just received a Pentax K and a Leica R to Q No-Name adapters for my Q7. Very low contrast and sharpness in all lenses I tested, even stopped down a bit. Well, sharpness improved, but still much lower contrast than I am used to. I then looked at the adapters. The exit holes are way to big for the tiny sensor. I installed baffles, two in each adapter, with a hole slightly bigger than the sensor, you know, like in a true telescope lens à la Leica Telyt or Novoflex Noflexar. Sharpness and contrast is now the way I like it. Lost 1&1/2 EV, but that was light destroying the image, not contributing to it. Stopped down, all lenses are razor sharp now. Favorites are Pentax 50mm 1.4, Leica R 60mm Elmarit Macro, Leica R 90mm Summicron and Leica R 180mm Elmarit. I expect to receive Pentax 100mm macro, 135mm 2.5 and 200mm 4.0 in just a few days, as I have ordered an adapter with shutter. Planning on doing some astrophotography soon. I'm just curious if anyone here is familiar with baffling the adapters? They are very poorly constructed regarding the cameras they are meant for. It took me half an hour and a sheet of black paper to get them right. I have searched the forum for a post regarding the issue, but could not find one. Sorry if this has been debated before.

Cheers!

Many have found the generic adapters to have interior black paint that was too reflective and so repainted or otherwise covered with a matte surface. That could be the problem rather than "holes too big", but your solution works either way I guess...

[NoRules]

Thanks for input! These adapters had nice rippled walls and matte paint. No excessive reflections. There was just a huge difference in contrast with baffles. Purple fringing was just gone, just the normal green/red longitudinal chromatic aberrations (LoCA) around branches against sky, easily removed in PP. If paint could do the trick, Leica and other lens makers would not use multiple baffles through-out a lens if that was the case. Here's the thing; even though the holes in my baffles was of same size, there was difference in using one or two. Even the thickness of the material used made a difference. The sensor of the Q7 is critically small, so every aspect matters. I did this experiment because I'm reading a book on lens design, and because I converted a lot of Konica lenses for 4/3 mount, where a smaller baffle is mandatory due to reflections in the mirror housing. Anyway, it's very easy to try, and the procedure is reversible.

[Steve.Ledger]

I installed baffles

Can you show us what you installed? I'm a little baffled by it

[lister6520]

The issue is not reflections by the adapter itself but rather reflection from the sensor to the rear element of the lens, and possibly its rear flange and back to the sensor. Baffles are indeed the only way to eliminate such reflections.
The gold plated contacts can also cause some severe flare when bright light from the lens falls on them. The problem is worst when using lenses with a large image circles, APS-C and larger.

I had wasted quite a lot of time trying to figure out why I had extreme flare when using a home made adapter with a Tamron 90mm macro. I painted and repainted and even coated the interior of the adapter with soot from a kerosene lamp - all to no avail. Then eventually I realised it was not the adapter reflecting but the camera itself and the lens.

[NoRules]

Thanks Lister6520. Then we agree, I think :-) Here is an image of what I did. I put one baffle in front and one in the back of the adapter. The point being that edges spread light like a lens, so the second baffle takes care of that diffraction from the edges of the first. Thats the theory anyway. Hope image show.

[vonBaloney]

I had wasted quite a lot of time trying to figure out why I had extreme flare when using a home made adapter with a Tamron 90mm macro.

Is that one of the Adaptall 90mm macros? Those are notorious for reflections because of the flat rear element...

[hnikesch]

I can see how the reflections are not a problem with the Pentax adapter, Gold contacts are used and covered by the adapter and the shutter is near the sensor and when open is smaller than your rear baffle hole. Sounds like a better fix than just painting the shutterless adapters. The ones I had all had large holes like yours

[dms]

I have heard that black flocking material (Edmond optical sells it, anyway used to) works well/better than flat black paint.

[Transit]

I just received a Pentax K and a Leica R to Q No-Name adapters for my Q7. Very low contrast and sharpness in all lenses I tested, even stopped down a bit. Well, sharpness improved, but still much lower contrast than I am used to. I then looked at the adapters. The exit holes are way to big for the tiny sensor. I installed baffles, two in each adapter, with a hole slightly bigger than the sensor, you know, like in a true telescope lens à la Leica Telyt or Novoflex Noflexar. Sharpness and contrast is now the way I like it. Lost 1&1/2 EV, but that was light destroying the image, not contributing to it. Stopped down, all lenses are razor sharp now. Favorites are Pentax 50mm 1.4, Leica R 60mm Elmarit Macro, Leica R 90mm Summicron and Leica R 180mm Elmarit. I expect to receive Pentax 100mm macro, 135mm 2.5 and 200mm 4.0 in just a few days, as I have ordered an adapter with shutter. Planning on doing some astrophotography soon. I'm just curious if anyone here is familiar with baffling the adapters? They are very poorly constructed regarding the cameras they are meant for. It took me half an hour and a sheet of black paper to get them right. I have searched the forum for a post regarding the issue, but could not find one. Sorry if this has been debated before.

Cheers!

Nice contribution to this ongoing process
Great first post too !

Pete

[Steve.Ledger]

Do you have any before and after shots?

[barondla]

Great research! You are correct about great lenses having baffles to reduce flare. They also paint the lens element edges, add special black paint, and flocking when required. Flare is tough to eliminate.

Before the oem Pentax Q-PK adapter was available, I used the RJ adapter. The image quality was mediocre. Painting the internals flat matte helped considerably. In tests the modified adaper was never able to match the Pentax made one. The shadow areas were never as black. This was also visible in the histogram.
thanks
barondla

[NoRules]

Do you have any before and after shots?

The best thing is to test yourself on your own subject matter with the lenses you normally use. Here are two images I did yesternight with the Leica Telyt R 400mm f.6.8. The lens has a series of baffles, and my Leica adapter has two. Camera is Q7.

[Steve.Ledger]

I was actually looking for comparison shots to tell if the effort of buying an adapter and then adding baffles would be worth my effort. But thanks any way

[NoRules]

I was actually looking for comparison shots to tell if the effort of buying an adapter and then adding baffles would be worth my effort. But thanks any way

Ok. I never like to do this. It's so subjective. Not sciensy at all. But here are two images taken a couple of hours apart for my own viewing, never intended to be a test. Pentax K 50mm f.1.4 at 1.4 with and without double baffles installed. Now, at the Olympus forum at DPreview, we had a long ongoing argument about baffles, aperture, light fall off, DOF, and so on back in 2005. As I said earlier, you loose about 1 1/2 EV, but looking at the much darker shadows and higher contrast, there is the explanation. Also, the light meter in the camera reacts when stopping down to f.2.0. It looks like the baffle is affecting the DOF, but it actually does not, and yet it does. Overall sharpness and contrast is increased, the blurring is almost gone, so subjectively the lens is going from being a soft focus lens to a regular lens, but in a scientific sense, DOF is not affected by the baffles. I think that was the consensus back then, the last time I had the debate. On the other hand, it's pointless. Everyone has to see for him or her self if this is a cool thing to do. Let images do the talking