Pentax-110 system film lenses on APS-C

Jean Poitiers · 05-17-2020, 12:50 AM - **2 Likes**

Originally posted by Rpats

Salut Jean,

Some great shots in this thread.

There are some comments about the video on DPReview to the effect that without some sort of aperture disc you are shooting with the lens "wide open" ie wider than the f/2.8 it was designed for and as a result image quality is degraded. Certainly I have found the bokeh unpleasant when I use the 18mm without an aperture. You don't mention this, have you not found it to be a problem?

Richard

Hi Richard,

Sorry to reply so late ... I really need to go back to the 18mm and experiment a bit more. I will report back later ...

Here's an image from yesterday with the 18mm that I installed a home-made aperture disc to try to create something like the hyper focal 18mm ... everything is in focal from about 7-8 feet to infinity ... taken with the Fuji X-E2 with post via Darktable 3.

Jean Poitiers · 05-17-2020, 02:14 AM - **4 Likes**

Another with the hyper focal Pentax-110 18mm on the X-E2.

Rpats · 05-17-2020, 11:22 PM

Hi Jean
Thanks for your reply, nice shots with the aperture disc in place.
Like you I am using a disc all the time now.
Richard

Jean Poitiers · 05-18-2020, 12:13 AM

Originally posted by Rpats

Hi Jean
Thanks for your reply, nice shots with the aperture disc in place.
Like you I am using a disc all the time now.
Richard

Hi there ... where have you placed your disc?

My first attempt was to use a paper hole reinforcer sticker which placed on the rear element ... Cheers, J

Rpats · 05-19-2020, 04:41 AM - **2 Likes**

Hi
I have one of those reinforcers on my 18mm.

Recently I got a close up lens for the 24mm, which I had not used much before, and found the rear opening on the lens was too big for the reinforcer. So I've inserted a cut down lens baby disc in the adapter to use with that. Hole is about 5mm. See example shot below

Richard

Jean Poitiers · 06-11-2020, 12:38 PM

Fujifilm X-E2 with my home-made hyper/pan focal Pentax-110 lens ... the 18mm with an added aperture disk in the middle of lens elements. Maybe f/8 ++ ... Here, a protest demonstration in Poitiers against racism.

Jean Poitiers · 07-28-2020, 12:02 PM - **6 Likes**

I just purchased a new Fujifilm X-T3 ... so on our day trip to Chambord, I took a few images with the 18mm that I home-made towards being a pan focal lens.

**UncleVanya** · 07-29-2020, 08:48 AM - **1 Like**

The last shot is stunning. They are all good but that one really is amazing.

Lhorn · 11-03-2020, 12:08 AM - **1 Like**

I'm very impressed with those pictures Jean. I originally bought my Lumix GH3 body for the sole purpose of getting more use out of my Auto 110 lenses. I was not horribly impressed with the sharpness off center. I've been shooting "wide open" so am interested in trying an aperture disk to see if I like the results better. It's simply a piece of piece of tape with a small, clean hole taped over the rear element? Other than the paper hole reinforcers anyone try other methods to punch holes of various sizes to be able to experiment with different size apertures?

**UncleVanya** · 11-03-2020, 08:38 AM - **1 Like**

Originally posted by Lhorn

I'm very impressed with those pictures Jean. I originally bought my Lumix GH3 body for the sole purpose of getting more use out of my Auto 110 lenses. I was not horribly impressed with the sharpness off center. I've been shooting "wide open" so am interested in trying an aperture disk to see if I like the results better. It's simply a piece of piece of tape with a small, clean hole taped over the rear element? Other than the paper hole reinforcers anyone try other methods to punch holes of various sizes to be able to experiment with different size apertures?

I've seen some use washers that fit tightly into the rear of the lenses.

Jean Poitiers · 11-03-2020, 09:27 AM - **1 Like**

Originally posted by Lhorn

I'm very impressed with those pictures Jean. I originally bought my Lumix GH3 body for the sole purpose of getting more use out of my Auto 110 lenses. I was not horribly impressed with the sharpness off center. I've been shooting "wide open" so am interested in trying an aperture disk to see if I like the results better. It's simply a piece of piece of tape with a small, clean hole taped over the rear element? Other than the paper hole reinforcers anyone try other methods to punch holes of various sizes to be able to experiment with different size apertures?

Hi,

I have tried several methods. First was to use a paper hole reinforcer that I had Sharpie blacked-out ... sticky-side stuck to the rear element housing. Another method is to use black rubber plumbing washers/grommets that are attached as well to the rear of the lens. My preferred option was to open the 18mm and insert a DIY aperture disk (thick black paper with hole via a small hobby punch) between the front and rear elements ... just like a movable aperture, but static and maybe about f/8+ at my best guess-timate. I may try to go smaller inserted DIY aperture on the 18mm ... I have a second copy which could be used, but I am happy with my first efforts.

Cheers, J

**UncleVanya** · 11-03-2020, 02:12 PM

Originally posted by Jean Poitiers

Hi,

I have tried several methods. First was to use a paper hole reinforcer that I had Sharpie blacked-out ... sticky-side stuck to the rear element housing. Another method is to use black rubber plumbing washers/grommets that are attached as well to the rear of the lens. My preferred option was to open the 18mm and insert a DIY aperture disk (thick black paper with hole via a small hobby punch) between the front and rear elements ... just like a movable aperture, but static and maybe about f/8+ at my best guess-timate. I may try to go smaller inserted DIY aperture on the 18mm ... I have a second copy which could be used, but I am happy with my first efforts.

Cheers, J

Did you make any comparison shots that you could share? If not, what makes you prefer this last method?

Lhorn · 11-04-2020, 09:48 AM

Is there a sense as to which of the three main lenses is the best, sharpest?

Jean Poitiers · 11-06-2020, 02:31 AM - **1 Like**

Originally posted by UncleVanya

Did you make any comparison shots that you could share? If not, what makes you prefer this last method?

Hi, I have no direct comparison shots to share at the moment, but I could do that with the 18/2.8 (normal) and the 18/? modified hyper-focal DIY. I have two 18's.

Maybe I should get a bit more technical in my work product.

I prefer the 18/8+ hyper focal DIY because the corners are a lot better than the 18/2.8. A lot better ... you lose a lot of light, but the trade-off for better corner sharpness is well worth it. My shots at Chambord Castle (above) really surprised me with their quality. I should try a bit of "lower" light situations to see the difference, if any.

Cheers, J

Jean Poitiers · 11-06-2020, 02:38 AM

Originally posted by Lhorn

Is there a sense as to which of the three main lenses is the best, sharpest?

Hi, without any modification, I would vote for the 50/2.8 ... best "all arounder" without any modification(s).

I like the center sharpness of the 24/2.8, but the edges are terrible. Maybe a "street" type lens if one is looking for this type of fall-off.

And as I wrote above, the 18mm is quite nice and a lot better modified to close it down a bit.

Cheers, J

06-11-2020, 12:38 PM	#51
Jean Poitiers Pentaxian Join Date: Apr 2011 Location: Lost in translation ... Photos: Gallery \| Albums Posts: 18,076 Original Poster	Fujifilm X-E2 with my home-made hyper/pan focal Pentax-110 lens ... the 18mm with an added aperture disk in the middle of lens elements. Maybe f/8 ++ ... Here, a protest demonstration in Poitiers against racism. Last edited by Jean Poitiers; 06-11-2020 at 12:44 PM.

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05-17-2020, 12:50 AM - 2 Likes	#46
Jean Poitiers Pentaxian Join Date: Apr 2011 Location: Lost in translation ... Photos: Gallery \| Albums Posts: 18,076 Original Poster	Originally posted by Rpats Salut Jean, Some great shots in this thread. There are some comments about the video on DPReview to the effect that without some sort of aperture disc you are shooting with the lens "wide open" ie wider than the f/2.8 it was designed for and as a result image quality is degraded. Certainly I have found the bokeh unpleasant when I use the 18mm without an aperture. You don't mention this, have you not found it to be a problem? Richard Hi Richard, Sorry to reply so late ... I really need to go back to the 18mm and experiment a bit more. I will report back later ... Here's an image from yesterday with the 18mm that I installed a home-made aperture disc to try to create something like the hyper focal 18mm ... everything is in focal from about 7-8 feet to infinity ... taken with the Fuji X-E2 with post via Darktable 3.

05-17-2020, 02:14 AM - 4 Likes	#47
Jean Poitiers Pentaxian Join Date: Apr 2011 Location: Lost in translation ... Photos: Gallery \| Albums Posts: 18,076 Original Poster	Another with the hyper focal Pentax-110 18mm on the X-E2.

05-17-2020, 11:22 PM	#48
Rpats New Member Join Date: Mar 2020 Posts: 8	Hi Jean Thanks for your reply, nice shots with the aperture disc in place. Like you I am using a disc all the time now. Richard

05-18-2020, 12:13 AM	#49
Jean Poitiers Pentaxian Join Date: Apr 2011 Location: Lost in translation ... Photos: Gallery \| Albums Posts: 18,076 Original Poster	Originally posted by Rpats Hi Jean Thanks for your reply, nice shots with the aperture disc in place. Like you I am using a disc all the time now. Richard Hi there ... where have you placed your disc? My first attempt was to use a paper hole reinforcer sticker which placed on the rear element ... Cheers, J

07-28-2020, 12:02 PM - 6 Likes	#52
Jean Poitiers Pentaxian Join Date: Apr 2011 Location: Lost in translation ... Photos: Gallery \| Albums Posts: 18,076 Original Poster	I just purchased a new Fujifilm X-T3 ... so on our day trip to Chambord, I took a few images with the 18mm that I home-made towards being a pan focal lens.

07-29-2020, 08:48 AM - 1 Like	#53
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,454	The last shot is stunning. They are all good but that one really is amazing.

11-03-2020, 12:08 AM - 1 Like	#54
Lhorn Veteran Member Join Date: Jan 2019 Posts: 554	I'm very impressed with those pictures Jean. I originally bought my Lumix GH3 body for the sole purpose of getting more use out of my Auto 110 lenses. I was not horribly impressed with the sharpness off center. I've been shooting "wide open" so am interested in trying an aperture disk to see if I like the results better. It's simply a piece of piece of tape with a small, clean hole taped over the rear element? Other than the paper hole reinforcers anyone try other methods to punch holes of various sizes to be able to experiment with different size apertures?

11-03-2020, 08:38 AM - 1 Like	#55
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,454	Originally posted by Lhorn I'm very impressed with those pictures Jean. I originally bought my Lumix GH3 body for the sole purpose of getting more use out of my Auto 110 lenses. I was not horribly impressed with the sharpness off center. I've been shooting "wide open" so am interested in trying an aperture disk to see if I like the results better. It's simply a piece of piece of tape with a small, clean hole taped over the rear element? Other than the paper hole reinforcers anyone try other methods to punch holes of various sizes to be able to experiment with different size apertures? I've seen some use washers that fit tightly into the rear of the lenses.

11-03-2020, 09:27 AM - 1 Like	#56
Jean Poitiers Pentaxian Join Date: Apr 2011 Location: Lost in translation ... Photos: Gallery \| Albums Posts: 18,076 Original Poster	Originally posted by Lhorn I'm very impressed with those pictures Jean. I originally bought my Lumix GH3 body for the sole purpose of getting more use out of my Auto 110 lenses. I was not horribly impressed with the sharpness off center. I've been shooting "wide open" so am interested in trying an aperture disk to see if I like the results better. It's simply a piece of piece of tape with a small, clean hole taped over the rear element? Other than the paper hole reinforcers anyone try other methods to punch holes of various sizes to be able to experiment with different size apertures? Hi, I have tried several methods. First was to use a paper hole reinforcer that I had Sharpie blacked-out ... sticky-side stuck to the rear element housing. Another method is to use black rubber plumbing washers/grommets that are attached as well to the rear of the lens. My preferred option was to open the 18mm and insert a DIY aperture disk (thick black paper with hole via a small hobby punch) between the front and rear elements ... just like a movable aperture, but static and maybe about f/8+ at my best guess-timate. I may try to go smaller inserted DIY aperture on the 18mm ... I have a second copy which could be used, but I am happy with my first efforts. Cheers, J

11-03-2020, 02:12 PM	#57
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,454	Originally posted by Jean Poitiers Hi, I have tried several methods. First was to use a paper hole reinforcer that I had Sharpie blacked-out ... sticky-side stuck to the rear element housing. Another method is to use black rubber plumbing washers/grommets that are attached as well to the rear of the lens. My preferred option was to open the 18mm and insert a DIY aperture disk (thick black paper with hole via a small hobby punch) between the front and rear elements ... just like a movable aperture, but static and maybe about f/8+ at my best guess-timate. I may try to go smaller inserted DIY aperture on the 18mm ... I have a second copy which could be used, but I am happy with my first efforts. Cheers, J Did you make any comparison shots that you could share? If not, what makes you prefer this last method?

11-04-2020, 09:48 AM	#58
Lhorn Veteran Member Join Date: Jan 2019 Posts: 554	Is there a sense as to which of the three main lenses is the best, sharpest?

11-06-2020, 02:31 AM - 1 Like	#59
Jean Poitiers Pentaxian Join Date: Apr 2011 Location: Lost in translation ... Photos: Gallery \| Albums Posts: 18,076 Original Poster	Originally posted by UncleVanya Did you make any comparison shots that you could share? If not, what makes you prefer this last method? Hi, I have no direct comparison shots to share at the moment, but I could do that with the 18/2.8 (normal) and the 18/? modified hyper-focal DIY. I have two 18's. Maybe I should get a bit more technical in my work product. I prefer the 18/8+ hyper focal DIY because the corners are a lot better than the 18/2.8. A lot better ... you lose a lot of light, but the trade-off for better corner sharpness is well worth it. My shots at Chambord Castle (above) really surprised me with their quality. I should try a bit of "lower" light situations to see the difference, if any. Cheers, J

11-06-2020, 02:38 AM	#60
Jean Poitiers Pentaxian Join Date: Apr 2011 Location: Lost in translation ... Photos: Gallery \| Albums Posts: 18,076 Original Poster	Originally posted by Lhorn Is there a sense as to which of the three main lenses is the best, sharpest? Hi, without any modification, I would vote for the 50/2.8 ... best "all arounder" without any modification(s). I like the center sharpness of the 24/2.8, but the edges are terrible. Maybe a "street" type lens if one is looking for this type of fall-off. And as I wrote above, the 18mm is quite nice and a lot better modified to close it down a bit. Cheers, J