Pentax 6X7 focussing screen Part 3

[Soeren]

Here we go again
I couldn't find much covering this
So The 6X7 finder is dim
A possible solution is a new screen e.g a Beattie screen.
Those are quite expensive so...
Whats to gain ? Equals how many F-stops ? They claim up to 3.
Any one got experience ?
Would you recommend microprism, split image or something else ?
Comments ?
Would you buy one ?
For the cost of such a screen I could buy a lens and the time it takes to have it fixed I could use to go shooting. I have no knowledge in this at all.
Regards Søren

 

[Mick Fagan]

About 10 years ago a friend bought an old Pentax 67, don't know which model, but it was old then.

He eventually purchased an aftermarket screen. I don't know which one, but it had a grid etched for compositional aid.

I have a Gossen Profi-six meter and one of the attachments I have is the fibre optic measuring unit. This allows one to use the Profi-six, to get TTL readings on the groundglass of a LF camera.

We tested his old focusing screen against the new one, the difference was approximately 1 and 1/3 of a stop brighter in the centre of the focusing screen.

I cannot be sure, but I think it was a Beattie screen.

At the time, I remember thinking I should get one for my Nikon F3, but the F3 screen was double the price of my FE2 screen, I couldn't think of any logical reason for this, so I didn't get one.

Mick.

 

[Soeren]

Thanks for your reply Mick.
Is This really it ? Out of 10000 + members only one have experience on whats to gain when changing focussingscreens.
Beatie Intenscreen say up to 3 F-stops. that must be some exaggeration but then again "up to..." covers a lot of ground.
And don't you care about which focussing aid it has ?
Cheers Søren

 

[ras351]

If you haven't already done so, pop the screen out and give it a wash in soapy water followed by a good rinse. Dust and dirt can significantly reduce the amount of light being transmitted. Give the mirror a clean. If you have a prism instead of the waist level finder, remove the prism and give it a clean. With the prism removed see if the image on the ground glass looks brighter than when looking through the prism and if so you may need to replace the prism instead of the ground glass. If you have a metering prism is it accurate and/or consistent with your other cameras?

I have a 67II and am happy with the brightness so can't comment on how much you'll gain by going to a Beattie screen. My personal preference is for a combination split image/microprism/gridded focussing aid but it's rare (if not impossible) to get all three on the one screen. I've made do with the microprism on my 6x7 although to be honest I prefer the split image in combination with a good ground glass but this is somewhat subjective.

Roger.

 

[Soeren]

Roger thank you for your reply.
I might have to send the camera of to a CLA since the screen does'nt just pop out.
I would need some special tools to remove it. I don't find the image much brighter without the prismfinder so....
Well I send it of to CLA and decide on the possible new focussing screen later.
regards Søren

 

[ras351]

Roger thank you for your reply.
I might have to send the camera of to a CLA since the screen does'nt just pop out.
I would need some special tools to remove it. I don't find the image much brighter without the prismfinder so....
Well I send it of to CLA and decide on the possible new focussing screen later.
regards Søren

The 67II screen has a plastic surround which latches fairly simply at the front and rear - it can be removed from the top at the rear with a fingernail. I'm surprised to hear the older models aren't similar.

Roger.

 

[Soeren]

The 67II screen has a plastic surround which latches fairly simply at the front and rear - it can be removed from the top at the rear with a fingernail. I'm surprised to hear the older models aren't similar.

Roger.

The story of improvement
The screen on the Pentax 6X7 is mounted with 4 screws, two of those requires a special tool to unscrew. The installation instruction on the Beattie website states that replacement should be carried out by authorized Pentax repair center, something about allignment.
Regards Søren

 

[paul ewins]

I had the standard screen in my 67 replaced with a grid screen. Since I was curious, the service tech showed me what needed doing. There is a separate fresnel taped to the screen (around the edges) and there is a spring/shim underneath to push it into place. It did look like it would need careful work to get it all aligned correctly. I am lucky enough to have the local Pentax distributor only 10 minutes walk away, so it is relatively cheap to get things fixed. Often they won't charge if they can't fix something which I am sure would be different if they had to post it back to me.