[Fenwoodian]

I did not put the original baffle back on the lens. The one you see in the photo is a completely new one that I made out of flat black posterboard.

As I previously said, I've made plenty of these homemade baffles in the past for other lenses and my "before and after" photos on these other lenses have shown me that these home made flat black baffles work great.

Anybody want one of my homemade flat black 60-250mm baffles? I made a template and can easily make lots of them in the exact shape and dimensions as mine...

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Last edited by Fenwoodian; 06-07-2016 at 11:51 AM.

[Gutta Perka]

I did not put the original baffle back. The one you see in the photo is a completely new one that I made out of flat black posterboard.

As I previously said, I've made plenty of these homemade baffles in the past for other lenses and my "before and after" photos on these other lenses have shown me that these home made flat black baffles work great.

Anybody want one of my homemade flat black 60-250mm baffles? I made a template and can easily make lots of them in the exact shape and dimensions as mine...

I do not need your baffles - in this thread we remove them/it.
That is what we wanted.

Having a hard time, sir?

"A tube is a tube - a baffle is a baffle"
A baffle is sitting in about 90 degrees from the main light-path.
The tube is parallel to the light-path.

That's it!

Again:
Some other thing - You could at least have thanked the OP of this thread for his observation and thoughts on your other sites on the Internet showing your success - for what You gained. Like a gentleman You know!

I might be wrong - You did this long before we did?

[jatrax]

Anybody want one of my homemade flat black 60-250mm baffles? I made a template and can easily make lots of them in the exact shape and dimensions as mine...

I won't presume to ask you to make one for me, but if it would not be too much trouble could you either post or PM me the dimensions used? I'll happily make my own. I've been following this and want to perform the mod, but wanted a way to make it reversible in case I eventually sell the lens. Sounds like you have the best solution to that @Fenwoodian. Thanks!

[Fenwoodian]

I won't presume to ask you to make one for me, but if it would not be too much trouble could you either post or PM me the dimensions used? I'll happily make my own. I've been following this and want to perform the mod, but wanted a way to make it reversible in case I eventually sell the lens. Sounds like you have the best solution to that @Fenwoodian. Thanks!

John, it's easier for me just to send you one because the optimum design for this custom full frame baffle is "curved".

The baffle's in the mail to you. In a private message I sent you some instructions too.

[jatrax]

The baffle's in the mail to you. In a private message I sent you some instructions too.

Thank you sir! Greatly appreciated.

[Gutta Perka]

I am very experienced at making my own baffles. I have made many of them for my MOG Diaplan lenses.

.....
Gutta, are you a believer now?

Fenwoodian, looking at Your photo of Your lens - why did You remove the contact next to the screw situated at about just before "nine a clock" - looking straight into end of the star 60-250.

There should be five plus one - You have modded and have four plus one.

Some extra features of Your own?

[VoiceOfReason]

I did not put the original baffle back on the lens. The one you see in the photo is a completely new one that I made out of flat black posterboard.

As I previously said, I've made plenty of these homemade baffles in the past for other lenses and my "before and after" photos on these other lenses have shown me that these home made flat black baffles work great.

Anybody want one of my homemade flat black 60-250mm baffles? I made a template and can easily make lots of them in the exact shape and dimensions as mine...

I am interested in example pics, especially toward light sources, and then interested in doing it to mine.

[jatrax]

I would like to thank @npc, @Gutta Perka, @Fenwoodian and the others in this thread that figured out this mod and how to do it. I am just going to lay out in detail the instructions with pictures for what they figured out.

NOTE: Do this at your own risk. You are working on a 'DA*' lens worth maybe $1,000. Think carefully if you want to take the chance of ruining your lens!!!!!!!!!

Here are some detailed instructions:

1. First, there is no need to remove the bayonet. Just the smaller plastic ring that holds the SDM contacts.
   
2. Locate the SDM contacts and remove the two small black screws there.
   
3. Gently pry out the black plastic SDM mount with the two gold contacts. These are slip fit connectors, like electrical connectors, so just gently pry on each side back and forth until it lifts out.
   
   
   
4. Locate the three silver screws holding the black ring in place. There are four screws in the ring. Three located at 120 degrees from each other and a fourth just to the right of one of the others. Of the pair you want the left one. Remove these three screws. I used a rear lens cap to put the pieces in to keep them safe. These are very small screws. They are also JIS so make sure you do not strip them.
   
5. Now with the screws out the black SDM ring and the baffle will just pull out in one piece.
   
6. The baffle is glued with something like rubber cement to the SDM ring. I used an Exacto razor knife to cut the glue away, but it was soft enough I think you could just break it. Note the scratches on the black baffle, these were present on the baffle when I removed it and were not caused by anything I did. Not sure if they are from manufacturing or if something was rubbing on it inside.
   
7. Now the baffle and the SDM ring are seperated, clean up any glue residue on the ring. I just used the razor knife.
   
8. Now we need to remount the SDM ring. Place the ring back in position, aligning the two rectangular holes with the two gold female SDM contacts. Replace the three silver screws.
   
9. Now gently replace the SDM contacts by pressing them slowly back into the female connectors. Replace the two black screws that hold the SDM contact plate in place.
10. Now insert the cardboard replacement baffle. Dimensions of the original are roughly 30mm wide so you need a cardboard strip a bit smaller than that and long enough to wrap around itself. I just rolled it up slightly tighter than needed, inserted it and let it unroll in place.
    
    
11. The project is done, put the lens on the camera and test. I gave myself nearly a heart attack as mine would no longer auto-focus. I forgot I had the camera in manual focus.

After brief testing I can say that most, but not all of the, vignette has been removed. Unfortunately it is dark and overcast today so difficult to do good testing. From what I see there is no vignette below 85mm and only a slight darkening in the corners above that. This is at f/4. The sharp circular vignette is completely gone and I do not think the lens is much worse in the corners now on FF than it was on APS-C.

[jake14mw]

Thanks so much Jatrax for adding these pictures! This makes it much easier for everyone to understand what is being discussed.

I don't know much about lens design, but I would think that any lens maker would be pretty precise as to how that baffle is designed. From what I can see from the pictures, the baffle consists of a long tube, and at the end closest to camera body, a circular "flange" that is parallel to the lens elements. I would guess that there is a purpose for this flange, or it would not be there. It seems to me, the best mod would be to remove the "corners" of this flange that cause the vignetting. I would love to see before and after pictures of the vignetting with the baffle in place and then removed.

Also, I love the ingenuity of crafting a custom baffle, but I would be concerned about tiny pieces of the cardboard eventually flaking off and causing trouble. Not sure of how much of a concern this should be. How does this tube stay still?

Thanks to everyone for their contributions to this thread. It's very interesting, I will follow with interest.

[Greyser]

Thank you guys for the wonderful hint. It did work for me.
There is a cross posting from DPReview/Pentax:

Modified DA*60-250/4 on K-1: Pentax SLR Talk Forum: Digital Photography Review

Please note that I did not separate the flange from the tube. I kept the whole assembly glued together when removing the flange.

[riseform]

Add another to the FF mod which I completed last night.

My sincere gratitude to those who went before, for their initial bravery and the multiple shared tips and excellent instructional pictures.

I copied Greyser's technique, keeping the baffle tube and SDM ring glued together as I permanently drilled away the flange with a Dremel cutting bur. I marked the raw edge with a black sharpie.

I'll be bringing this lens along with the K1 to South Georgia Island next month. Bring on the penguins!

[mattb123]

Thanks so much Jatrax for adding these pictures! This makes it much easier for everyone to understand what is being discussed.

I don't know much about lens design, but I would think that any lens maker would be pretty precise as to how that baffle is designed. From what I can see from the pictures, the baffle consists of a long tube, and at the end closest to camera body, a circular "flange" that is parallel to the lens elements. I would guess that there is a purpose for this flange, or it would not be there. It seems to me, the best mod would be to remove the "corners" of this flange that cause the vignetting. I would love to see before and after pictures of the vignetting with the baffle in place and then removed.

Also, I love the ingenuity of crafting a custom baffle, but I would be concerned about tiny pieces of the cardboard eventually flaking off and causing trouble. Not sure of how much of a concern this should be. How does this tube stay still?

Thanks to everyone for their contributions to this thread. It's very interesting, I will follow with interest.

Interesting idea about just cutting the corners. Anyone try that yet?

[bdery]

I copied Greyser's technique, keeping the baffle tube and SDM ring glued together as I permanently drilled away the flange with a Dremel cutting bur. I marked the raw edge with a black sharpie.

I'm trying to understand this, as I'm really not comfortable inserting paper or cardboard inside a lens. I'd rather dremel out a small part of the lens, but I want to understand the process beforehand.

I took the images from jatrax's wonderful post (thanks, at last a visual explanation) and added red on the part that I think I must grind. If anyone can confirm that this is correct, I'd be a happy camper (and I can decide if I want to make the modification or not).

Thanks!

[mattb123]

I'm trying to understand this, as I'm really not comfortable inserting paper or cardboard inside a lens. I'd rather dremel out a small part of the lens, but I want to understand the process beforehand.

I took the images from jatrax's wonderful post (thanks, at last a visual explanation) and added red on the part that I think I must grind. If anyone can confirm that this is correct, I'd be a happy camper (and I can decide if I want to make the modification or not).

Thanks!

That is my understanding. Or you could just cut out triangles only for the parts that block the corners of the frame and leave most of the rest. I may try that approach but I'm getting my 60-250 repaired so it will focus again first.

[jatrax]

I'd rather dremel out a small part of the lens, but I want to understand the process beforehand.

As I understand it, that is correct. The baffle tube itself is fine, it is that flange at the bottom that causes the problem. So cutting that out should achieve the same thing. I went the other way by removing the tube intact, thus preserving it for re-installation if needed. I also felt uncomfortable with using a dremel tool to cut it out. However, if you have the tool skills I do not see why it would not work.

Basic caution about using cutting tools, getting metal shavings in the lens and so on all understood.