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Forum: Mini-Challenges, Games, and Photo Stories 2 Days Ago  
Game Song titles (or lyrics) illustrated
Posted By Thagomizer
Replies: 202
Views: 4,198
Thanks! I'm glad you're enjoying it. Thanks for contributing!
Forum: Mini-Challenges, Games, and Photo Stories 6 Days Ago  
Thematic The Yard Birds Thread
Posted By Thagomizer
Replies: 1,758
Views: 111,394
Please do!
Forum: Mini-Challenges, Games, and Photo Stories 6 Days Ago  
Show me a Sign! Billboards,sign,bus ads,shop signs go here!
Posted By Thagomizer
Replies: 5,439
Views: 424,409
So, 30 points for each one?
Forum: Non-Pentax Cameras: Canon, Nikon, etc. 6 Days Ago  
Got Squirrel Shots? (In memorial of Rupert)
Posted By Thagomizer
Replies: 2,639
Views: 209,806
Perhaps if you were to dress as a large peanut...
Forum: Mini-Challenges, Games, and Photo Stories 6 Days Ago  
Game Song titles (or lyrics) illustrated
Posted By Thagomizer
Replies: 202
Views: 4,198
Were you sitting on a cornflake when you took this one?
Forum: Mini-Challenges, Games, and Photo Stories 6 Days Ago  
Thematic The Yard Birds Thread
Posted By Thagomizer
Replies: 1,758
Views: 111,394
Great series!
Forum: Mini-Challenges, Games, and Photo Stories 6 Days Ago  
Thematic Good as Gold
Posted By Thagomizer
Replies: 211
Views: 4,361
I like the ghostly, indistinct reflections of the spectators in the side panels.
Forum: Pentax SLR Lens Discussion 02-05-2020, 01:23 PM  
Opinion time: what are your favorite manual lenses?
Posted By Thagomizer
Replies: 176
Views: 9,520
I've got one I'll have to play with more; I haven't really given it a good workout. It's a bit beat up; I had to replace the rubber grip on the zoom ring, but other than some abrasions on the finish, seems to be okay.
Forum: Lens Clubs 01-31-2020, 07:04 PM  
The Mirror Lens Club!
Posted By Thagomizer
Replies: 1,137
Views: 402,943
Yes, my 55BB behaves much better in bright sunlight.

The cardinal and bunny are quite good.
Forum: Mini-Challenges, Games, and Photo Stories 01-30-2020, 01:27 PM  
Thematic Look down, awaaay down...
Posted By Thagomizer
Replies: 249
Views: 5,964
tim-berrrr!!!
Forum: Pentax KP 01-30-2020, 09:15 AM  
Focus adjustment using Manual Lenses in U4 mode
Posted By Thagomizer
Replies: 9
Views: 435
You might find this article, posted a few days ago, helpful:Achieving Better Manual Focus with the Green Hexagon - PentaxForums.com
Forum: Pentax K-1 01-30-2020, 08:53 AM  
How bad of a thing is mirror flap?
Posted By Thagomizer
Replies: 13
Views: 596
I didn't know that! That's good information to have, thanks!
Forum: Lens Clubs 01-23-2020, 12:45 PM  
Macro by any means necessary club
Posted By Thagomizer
Replies: 540
Views: 107,568
I've never done any real testing on any of my many macro set-ups to see at what point diffraction becomes objectionable. What smaller aperture giveth in DOF, diffraction taketh away in clarity. At some aperture one reaches the point of diminishing returns. I'm guessing that point can vary from lens to lens (and photographer to photographer...). Focus stacking lets you use any given lens at its optimum aperture without regard to DOF, which is essentially synthesized in the stack. Those shooters like myself who are doing single shots instead of stacks have decide where that trade-off point between desired DOF gain and unacceptable diffraction loss is.
Forum: Lens Clubs 01-23-2020, 11:50 AM  
Macro by any means necessary club
Posted By Thagomizer
Replies: 540
Views: 107,568
Well that's good to know. I'm no optical expert; I'd rather understate than oversell. I'm happy to bring attention to the lens, and if it works better for stacking or other applications than I'm giving it credit for, so much the better (and shame on me!:D). I did notice the lack of CA, but I thought the sharpness wasn't quite there, and I thought that it could be diffraction rearing its ugly head. The thin depth of field might make whatever sharpness there is less obvious amidst the softness in front of and beyond the plane that is in focus. I certainly would be curious to see how it would work as a tool in a focus stacking rig. Unfortunately I don't have any stacking software, and my computer would probably choke to death on the throughput of data that would require.

I still have yet to try the 03 as the front element of a wide angle macro relay lens. I've got a selection of wide angle primes and zooms to use as the relay optic that, along with the right extension, will (with any luck) throw an image that gives APS-C coverage. I'm hoping that the 03 will offer better image quality than the cheap M12 board lenses I've seen used very effectively by others. We'll see what happens...
Forum: Pentax Q 01-23-2020, 10:21 AM  
Reversed 03 fish-eye on KP
Posted By Thagomizer
Replies: 14
Views: 771
More results from the reversed Q 03 fish-eye on my KP. I'm posting this on all three threads where I've been talking about this; "Reversed 03 fish-eye on KP", "Pentax Q mount macro reverse rings", and "Macro by any means necessary club."

Camera is tripod mounted on a focus rail. Electronic shutter with 12 second self timer for shooting, existing light using a diffused Ikea Jansjo light.

First some more "indutrial" targets. Printed number on a lens barrel:




Printing on a business card:





The edges of some small manilla envelopes:




Still industrial, but not mechanical. Multigrain bread...



and the surface of one of the seeds on the top of the bread.



Some closeup bug bits.

Our first subject, an unfortunate shield bug (?), which I found dead in a corner of the bedroom, under some stuff.

Here's the whole insect:



And a close-up of its eye:



Our second contestant is a cast-off cicada husk:



Some of its bits. The business end of one of its digging claws:



And spines at the (wrist? elbow??) joint of the same limb:



An adult cicada (found deceased).



A close-up of one of its eyes:



Because of the very limited depth of field, reversing the Q 03 fish-eye might best be used with flat subjects. More three dimensional subjects move out of the limited plane of focus very quickly in either direction; image quality is such that it might not be worth the trouble of stacking, though I'll let those who actually do focus stacking (of which I am not, as yet, one) decide this for themselves. I don't think this optic is a hidden gem that's going to take the photomacrography world by storm. That said, it is fun to play with and makes for a comparatively compact rig for high magnification shooting. If I'm feeling particularly optimistic (or masochistic) I might even try it in the field once weather is warmer.
Forum: Pentax Q 01-23-2020, 10:21 AM  
Pentax Q mount macro reverse rings
Posted By Thagomizer
Replies: 19
Views: 1,512
More results from the reversed Q 03 fish-eye on my KP. I'm posting this on all three threads where I've been talking about this; "Reversed 03 fish-eye on KP", "Pentax Q mount macro reverse rings", and "Macro by any means necessary club."

Camera is tripod mounted on a focus rail. Electronic shutter with 12 second self timer for shooting, existing light using a diffused Ikea Jansjo light.

First some more "indutrial" targets. Printed number on a lens barrel:




Printing on a business card:





The edges of some small manilla envelopes:




Still industrial, but not mechanical. Multigrain bread...



and the surface of one of the seeds on the top of the bread.



Some closeup bug bits.

Our first subject, an unfortunate shield bug (?), which I found dead in a corner of the bedroom, under some stuff.

Here's the whole insect:



And a close-up of its eye:



Our second contestant is a cast-off cicada husk:



Some of its bits. The business end of one of its digging claws:



And spines at the (wrist? elbow??) joint of the same limb:



An adult cicada (found deceased).



A close-up of one of its eyes:



Because of the very limited depth of field, reversing the Q 03 fish-eye might best be used with flat subjects. More three dimensional subjects move out of the limited plane of focus very quickly in either direction; image quality is such that it might not be worth the trouble of stacking, though I'll let those who actually do focus stacking (of which I am not, as yet, one) decide this for themselves. I don't think this optic is a hidden gem that's going to take the photomacrography world by storm. That said, it is fun to play with and makes for a comparatively compact rig for high magnification shooting. If I'm feeling particularly optimistic (or masochistic) I might even try it in the field once weather is warmer.
Forum: Lens Clubs 01-23-2020, 10:21 AM  
Macro by any means necessary club
Posted By Thagomizer
Replies: 540
Views: 107,568
More results from the reversed Q 03 fish-eye on my KP. I'm posting this on all three threads where I've been talking about this; "Reversed 03 fish-eye on KP", "Pentax Q mount macro reverse rings", and "Macro by any means necessary club."

Camera is tripod mounted on a focus rail. Electronic shutter with 12 second self timer for shooting, existing light using a diffused Ikea Jansjo light.

First some more "indutrial" targets. Printed number on a lens barrel:




Printing on a business card:





The edges of some small manilla envelopes:




Still industrial, but not mechanical. Multigrain bread...



and the surface of one of the seeds on the top of the bread.



Some closeup bug bits.

Our first subject, an unfortunate shield bug (?), which I found dead in a corner of the bedroom, under some stuff.

Here's the whole insect:



And a close-up of its eye:



Our second contestant is a cast-off cicada husk:



Some of its bits. The business end of one of its digging claws:



And spines at the (wrist? elbow??) joint of the same limb:



An adult cicada (found deceased).



A close-up of one of its eyes:



Because of the very limited depth of field, reversing the Q 03 fish-eye might best be used with flat subjects. More three dimensional subjects move out of the limited plane of focus very quickly in either direction; image quality is such that it might not be worth the trouble of stacking, though I'll let those who actually do focus stacking (of which I am not, as yet, one) decide this for themselves. I don't think this optic is a hidden gem that's going to take the photomacrography world by storm. That said, it is fun to play with and makes for a comparatively compact rig for high magnification shooting. If I'm feeling particularly optimistic (or masochistic) I might even try it in the field once weather is warmer.
Forum: Pentax Q 01-21-2020, 10:41 PM  
Pentax Q mount macro reverse rings
Posted By Thagomizer
Replies: 19
Views: 1,512
You're welcome! Certainly better than I expected as well. I'm going to be trying it with a set-up that includes a tripod, flash (or at least better light, probably my Ikea Jansjo) with diffusion, and a focus rail. I'll post my results here when I do.
Forum: Mini-Challenges, Games, and Photo Stories 01-21-2020, 06:39 PM  
Game Stupid Camera Tricks (and Stupid Lens Tricks)
Posted By Thagomizer
Replies: 156
Views: 8,538
Neat result from a happy accident!
Forum: Pentax Q 01-21-2020, 06:37 PM  
Reversed 03 fish-eye on KP
Posted By Thagomizer
Replies: 14
Views: 771
Thanks! Good information on dealing with the shutter/aperture. Similar to the workaround I've heard of for Canon EOS lenses.

I don't have a Q body, but it looks like a neat system. Thanks everyone for indulging this Pentax APS-C shooter's tinkering!
Forum: Pentax Q 01-21-2020, 06:15 PM  
Pentax Q mount macro reverse rings
Posted By Thagomizer
Replies: 19
Views: 1,512
I just discovered this thread. Cool item! I'm not a Q body shooter, but I've reversed a Q 03 fish-eye. Even though it lacks filter threads, I managed to mount it on my KP using a 37-49 step-up ring and a K-mount 49mm reverse adapter. I put a bit of masking tape around the front of the lens barrel for a snug fit in the 37mm end of the stepping ring.



There might be a combination of stepping rings that would let you mount it on a Q body using the Q mount reverse adapter which is the subject of this thread. No lens shutter or aperture to worry about, either.

I was pleasantly suprised with the results. This is a close-up of half-tone printing on a laser printed price tag:




I've put up a thread here on the Q forum here: Reversed 03 fish-eye on KP - PentaxForums.com
Forum: Pentax Q 01-21-2020, 05:43 PM  
Reversed 03 fish-eye on KP
Posted By Thagomizer
Replies: 14
Views: 771
Good to know. I thought it might be the case, as my reversed Kinotel 1 1/2 inch 8mm covers APS-c without extension, but I didn't know for sure.

I'm assuming like DSLR lenses without aperture rings that the Q 01 standard prime (and the rest of the Q lens line-up, excluding the toy lenses) stays closed when not mounted on a body? Without the mechanical linkage that can be wedged open, there would be no way (without a lot of slaving over a hot soldering iron to put together some means for communication) to get a larger aperture. I'm lucky the 03 doesn't have a diaphragm to worry about. The toy lenses, which I assume also have no diaphragm, would be darker still. Looks like I fell into the right optic!

I think the 03 as the front end of a wide angle macro relay rig is going to take a bit more experimentation...

---------- Post added 01-21-20 at 08:03 PM ----------

P.S. Just found this thread (pretty recent, too) on reversing Q lenses on Q bodies: Pentax Q mount macro reverse rings - PentaxForums.com
Forum: Pentax Q 01-21-2020, 04:19 PM  
Reversed 03 fish-eye on KP
Posted By Thagomizer
Replies: 14
Views: 771
Thanks everyone!

I'd toyed with the idea of the Q 03 for a while. Holding one up to my eye and looking through it in reverse was VERY dark. I really couldn't make out anything using this quick inspection method, so I didn't bother trying it.



Thanks! For me, it felt like a logical progression. Having seen what the higher and higher magnification I got with with reversing wider and wider zooms (28-80, 18-55, 10-20), I figured something wider still would yield even more. So, I finally got hold of the 03 at a very good price. Actually, I bought it after I took these test shots. I was very pleased that mounting was so easy, and that the image circle gave full coverage on my KP.

---------- Post added 01-21-20 at 06:23 PM ----------



I was pleasantly suprised too, given the slap-dash, down & dirty test set-up I used for proof of concept. I'll have to see if I can eak out any more image quality with greater care. I don't think it's ever going to be for pixel peeping. At this point I'm not focus stacking either, so whether it would be good enough for that techniques is an open question.

---------- Post added 01-21-20 at 06:25 PM ----------



Ooops. Sorry! At least it won't take up much space...:lol:

---------- Post added 01-21-20 at 06:35 PM ----------



I haven't done any proper measurement, but it looks like the horizontal field of view is about 1.3mm. Spread out over the KP sensor size of 23.5mm gives a magnification of approximately 18X. I did take a few shots with a bit of extension; I don't think the ruler shot was one of them, but It's possible it was. In that case, magnification would be a bit less (see above about being more careful...;).
Forum: Lens Clubs 01-21-2020, 01:45 PM  
Macro by any means necessary club
Posted By Thagomizer
Replies: 540
Views: 107,568
(Cross posted with the Q forum)

Having reversed SLR lenses (prime and zoom), and movie camera lenses for macro shooting, I wondered about the Q 03 fish-eye, reversed, figuring that its short focal length would produce even higher magnification than nanything I'd yet tried reversing. So, I got a hold of one. I attached it to my KP using a 49mm reverse adapter, a 37-49mm step up ring, and some masking tape around the front barrel of the lens to keep it snug in the step up ring. No extension is necessary to get the image circle to fill the APS-C frame. I don't know what would happen with full frame, though.

The combination isn't going to win any beauty contests...



It works, but it's very tricky. DOF is minimal. Working distance is very small, 9.2mm, the registration distance of the Q. For these test shots I used existing light, live view and self-timer. Getting flash illumination on the subject will be tricky. It's unlikely I would use this in my usual hand-held field shooting style. This set up is going to need a tripod.





Some results.

Horizontal field of view is less than 2mm. Here are a pair of millimeter marks on a ruler:




The knurled focus ring of the 8mm cine lens seen in the shots above:



Printing from a step-up ring box. The box was not quite squiare on; the left hand side of the image is sharper than the right.



and the price tag on it.



Here's a shot of the box with a ruler. The black and orange pattern in the shot above is just to the left of the price tag.



I'll have to try this out on more interesting subjects. I'll post results when I do!

I also want to try the 03 fish-eye as part of a wide angle macro relay system. These rigs tend to use small M12 "board" lenses (usually with larger maximum apertures than the 03 has), intended for smaller sensor CCTV or GoPro style cameras and the like. Watch this space for developments...
Forum: Pentax Q 01-21-2020, 01:44 PM  
Reversed 03 fish-eye on KP
Posted By Thagomizer
Replies: 14
Views: 771
Here's a Q lens used on a non-Q body. Cross posted with the "Macro by any means necessary" thread.

Having reversed SLR lenses (prime and zoom), and movie camera lenses for macro shooting, I wondered about the Q 03 fish-eye, reversed, figuring that its short focal length would produce even higher magnification than nanything I'd yet tried reversing. So, I got a hold of one. I attached it to my KP using a 49mm reverse adapter, a 37-49mm step up ring, and some masking tape around the front barrel of the lens to keep it snug in the step up ring. No extension is necessary to get the image circle to fill the APS-C frame. I don't know what would happen with full frame, though.

The combination isn't going to win any beauty contests...



It works, but it's very tricky. DOF is minimal. Working distance is very small, 9.2mm, the registration distance of the Q. For these test shots I used existing light, live view and self-timer. Getting flash illumination on the subject will be tricky. It's unlikely I would use this in my usual hand-held field shooting style. This set up is going to need a tripod.





Some results.

Horizontal field of view is less than 2mm. Here are a pair of millimeter marks on a ruler:




The knurled focus ring of the 8mm cine lens seen in the shots above:



Printing from a step-up ring box. The box was not quite squiare on; the left hand side of the image is sharper than the right.



and the price tag on it.



Here's a shot of the box with a ruler. The black and orange pattern in the shot above is just to the left of the price tag.



I'll have to try this out on more interesting subjects. I'll post results when I do!

I also want to try the 03 fish-eye as part of a wide angle macro relay system. These rigs tend to use small M12 "board" lenses (usually with larger maximum apertures than the 03 has), intended for smaller sensor CCTV or GoPro style cameras and the like. Watch this space for developments...
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