• Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.

    Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

Out of depth with Leica? (1 Viewer)

John Cantelo

John Cantelo

Well-known member
Out of depth with Leica?

I recently bought a Leica 62 APO with a x32WA eyepiece. As everyone agrees, it's a very bright and "contrasty" scope. However, I find the depth of field so shallow that it's a real pain to focus. It's not so bad when birds are close and it's easy to see when the image is at its crispest and clearest, but peering at a bird in the distance it isn't so easy to judge. So is it just me? Perhaps others suffer the same problem? Or maybe I've got a 'Friday afternoon lemon',
John
 
John Cantelo said:
Out of depth with Leica?

I recently bought a Leica 62 APO with a x32WA eyepiece. As everyone agrees, it's a very bright and "contrasty" scope. However, I find the depth of field so shallow that it's a real pain to focus. It's not so bad when birds are close and it's easy to see when the image is at its crispest and clearest, but peering at a bird in the distance it isn't so easy to judge. So is it just me? Perhaps others suffer the same problem? Or maybe I've got a 'Friday afternoon lemon',
John
Click to expand...

Hi John,

It might help to compare your Leica 62 with other spotting scopes, maybe at the binocular store or in the field with other birder's spotting scopes. You could see if there is much of difference in depth of field.

Rich
 
I can't speak for the Leica, but my Nikon ED82 suffers from the same thing; it has no depth of field whatsoever. I'm wondering whether that's the price you have to pay for razor-sharp resolution.
 
Curtis Croulet said:
Shallow depth-of-field is going to be intrinsic with such a scope. It's not a defect.
Click to expand...

Yup. Through my Leica 77mm scope + 32 xw the DOF is indeed small, and focussing is critical. That is the price you pay for the extra magnification. I sometimes like to use a 20xw eyepiece as the DOF and hence ease of viewing are much greater. It's also easier to pick up birds in flight with the 20xw.

Incidentally on the 62mm scope the 32xw eyepiece gives 26x.
 
There are a couple of ways at the design stage to squeeze a bit more depth of field from a given aperture telescope at a given magnification. One is to increase the focal length of the objective. The Nikon 60mm fieldscope and the Swaro 65mm do that compared to most of the competitionin by using f/7 objectives. The other is to use an eyepiece design that incorporates a Barlow element so that the ocular has greater depth of field when it focuses on the aerial image from the objective. Most zoom eyepieces work that way as well as some lomg eye relief fixed magnification eyepieces, like the Nikon 30/38X, 40/50x and 60/75x,the Swaro 45x and the Zeiss 30/40X.
 
I found the same problem with the ED111A John but not so much with the ATS65HD. The Nikon focus ring goes from Zero to infinity in one turn, the Swarovski does the same in more than two turns. Would this finer adjustment give better focussing control and do you notice much difference with your coarse and fine adjustments.
 
Hi Henry,

as I read your posting, am I right to understand that - all other things being equal - a problem with wafer-thin DOF is going to be less of a problem with a decent zoom EP?

I ask because I've been wavering in my revolve to buy the zoom EP when I buy my new Zeiss scope, but your observation(!), if I read you correctly, might be just what I need to see to put the zoom back at the top of my shopping list...
 
blythkeith said:
Hi Henry,

as I read your posting, am I right to understand that - all other things being equal - a problem with wafer-thin DOF is going to be less of a problem with a decent zoom EP?

I ask because I've been wavering in my revolve to buy the zoom EP when I buy my new Zeiss scope, but your observation(!), if I read you correctly, might be just what I need to see to put the zoom back at the top of my shopping list...
Click to expand...

Keith,

Just compared the Zeiss zoom to the Zeiss 23/30X (which I notice also has a dedicated Barlow built in like the 30/40X) on my Astro-Physics scope. Results ought to be similar in the Diascope. The zoom set at 23/30X has a little more DOF than the 23/30XW, but not much. Even so I agree with Scampo that the field width with this zoom is so wide over most of it's range that fixed magnification wide field eyepieces just don't have the same advantage over the zoom in the Diascope that they have in other scopes with narrow field zooms.

Henry
 
Last edited:
Thank you kindly for the trouble you took Henry - it's much appreciated.

Looks like the benefits of the zoom will outweigh the doubts I was having - that wide FOV is very appealing.
 
Warning! This thread is more than 20 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.

Similar threads

J
Better understanding the Leica range for a second-hand purchase
Replies
15
Views
1K
jb b
J
Will K
Leica APO Televid 82 - first impressions
Replies
5
Views
2K
Will K
Will K
Craig H
Spotting Scopes - Personal needs and perceptions vs optical ability
Replies
6
Views
2K
Craig H
Craig H
Will K
My First Leica
Replies
7
Views
1K
jb b
J
R
DBA VHD+ 8x42 Monocular
Replies
2
Views
718
wm.wragg
W

Users who are viewing this thread

Total: 2 (members: 0, guests: 2)
Back
Top