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ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

Zeiss Jenna Delactis 8x40...rebuilt over the weekend (1 Viewer)

Rathaus

Rathaus

Well-known member
I picked these up on Saturday morning at a junk shop and then spent the entire weekend disassembling them, cleaning and rebuilding. I have never experienced such tightly torqued eye pieces or objectives, set into place no doubt over many many decades....I had no idea how old these things are.

Initially, the view was almost completely obscured by internal coatings of filth, but more importantly for me - the collimation was absolutely perfect, and the apparent fov was massive.

Once I got these back home, I just couldn't budge either objective. They were set rock solid. I set up a strap type wrench using my leather belt and a spanner (much longer than in the photo)...similar to some universal oil filter wrenches. I've done rear wheel adjustment on my 1400cc chain drive road motorcycle with a short wrench from the bike kit (while on a ride)...it needs 100nm, plus stiction...these bins were massively more difficult to budge. Even the IF eye pieces took far more than 100nm to budge. I couldn't believe they weren't ruined in the process, instead they remained perfect.

It took me two days to rid these things of filth and I have to say they are Lovely binoculars. Removing the The filth seemed never ending. I read they have an apparent fov of 70deg which was another reason I bought them to fix.

Otherwise I know nothing about these Zeiss! I'm reading up on them now and was shocked to read they started making them in ~1921?

Eventually I was able access every glass to air surface for thorough cleaning. These bins are now in superb and smooth working order. The prisms in these bins fit so deftly and sublimely into place.

I'm doing my own research, but If anybody can add any info about these it'd be appreciated. Here are a few pics of them.

Cheers
 

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This spanner didn't give enough leverage...it finally budged with a spanner a few inches longer. I use a Warren Brown torque wrench on the motorcycle rear wheel nut etc so I'm familiar with some settings.
 

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Hi Rathaus,

congratulations to a nice find. Your pair was made in 1925 and the Delactis was the first non-military model with Erfle eyepieces (Heinrich Erfle was head of the telescope section at Zeiss from 1918 on).

Joachim
 
jring said:
Hi Rathaus,

congratulations to a nice find. Your pair was made in 1925 and the Delactis was the first non-military model with Erfle eyepieces (Heinrich Erfle was head of the telescope section at Zeiss from 1918 on).

Joachim
Click to expand...

Joachim

Thanks so much for that. I'm just astounded at that date. So, these bins are 91years old. I'm trying to get my head around that. To my eyes they look so...contemporary. Everything is silky smooth yet firm in operation.

Here is another shot which better shows off the quality of the eye piece structure. Everything is beautifully machined.
 

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And here is a clean objective. I had to be quite firm with the cleaning process and they just started to shine. In my hands, I've never before seen such grubby glass become so beautiful.
Looking at familiar pine needles and the tip of a tree two hundred metres away I can easily count the familiar buds growing on the apex. Very very easy on the eyes, perhaps due to the perfect collimation and the 5mm exit pupil..and that 70deg afov.

I'm having to remind myself, I could barely discern or see anything through these bins two days ago...just dirty dim brown light and only just enough to test collimation. Many parts of these bins are hand etched with codes etc. absolutely everything is metal and glass, which makes sense since plastic wasn't mass produced at the time.
 

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if you try that on newer models you will have to be more delicate in the cleaning process....or you will scratch the coatings.....very nice job by the way....
 
gunut said:
if you try that on newer models you will have to be more delicate in the cleaning process....or you will scratch the coatings.....very nice job by the way....
Click to expand...

Thanks, and good point about cleaning coated optics. It makes me wonder if a coated optic in such a ruinous and ingrained filthy state could possibly be cleaned/restored at all?
 
I just purchased one of these and I am so grateful for all of this information on them. I really don't need another pair of vintage Zeiss but the eyepieces looked really interesting. Zeiss binoculars are like potato chips, you can't stop after the first one. I can't wait to compare these with my Zeiss Jena 8x30W with the multi-coatings. Those are one of my favorites, just so light and well-balanced, truly a delight to use.
 
Rathaus hasn't logged on for some time - if you're reading this sir, I hope you're well and enjoying your collection. Some time ago you commented that the Habicht required some technique and practice to use - something that really squares with my own experience of porros (maybe it's adjusting to the wider spread of the objectives) all the way from the old 8x30 Oberkochen to the Nikon SE.

I wonder whether the vintage Zeiss 8x40 model Mr Suddarth apparently plans to have multi-coated (see link) is one of these, or the one with the even wider field of view. Either way, it'll be interesting to see what the results are. Presumably (?) it would be more straightforward to apply multi-coatings to completely uncoated lenses/prisms as compared to glass that has already been single-coated? Coated or not, it'll still be a heavy beast for an 8x40 (1.2kg+), being made from brass (!), but for those amongst us who can shrug off the weight...

It'll be interesting to hear some opinions on how these compare to American or Japanese widefield 8x40s of the post-war era, such as the Linet I recall elkcub once showing us. Was the Swift Saratoga based on an American model?

The one being advertised up-thread on ebay looks like it's in great condition, yet it's almost too nice - one accident would ruin that immaculate exterior. One wonders sometimes when looking at old binoculars like that how often they were used, and much enjoyment their owners truly got out of them.
 
Does anyone happen to know what the field of view is for the Carl Zeiss Jena 8x40 Delactis? I thought I read something stating 8.5°? I might be confusing this with the field of view for the 8x30W Zeiss Jena binoculars though. I can't wait to compare these two. I can hardly contain my excitement, they look to be in good used condition with the leather case. I love and adore my 8x30W with the multi-coatings, they're so light and well-balanced I can use them all day. Would anyone happen to know the specs for the Delactis? I want to make sure I get all of the details correct for my review. I'll also be comparing them with my Bushnell Rangemaster binoculars which are also extremely good. Very heavy though and not quite as sharp or as bright as the Zeiss Jena 8x30W though. I so enjoy sitting back to watch the local wildlife with binoculars, it has become quite the addiction!
 
dries1 said:
Check these bad boys out, forget the cost etc. just to appreciate something of this age looking brand new.

www.ebay.com

DELACTIS 8X40 BINOCULARS w/CASE, compass CARL ZEISS JENA Outstanding Condition | eBay

Find many great new & used options and get the best deals for DELACTIS 8X40 BINOCULARS w/CASE, compass CARL ZEISS JENA Outstanding Condition at the best online prices at eBay! Free shipping for many products!
www.ebay.com

Andy W.
Click to expand...
Hi. I’m the owner of the binoculars in the photo. I was selling them on eBay last year until a potential buyer spotted an incorrect font used on the number “4” in the 8x40 marking. As such I took down the listing and investigated further and found the font for “Carl Zeiss Jena” in the logo to be incorrect as well so I concluded they are high quality fakes which I have yet to verify with Zeiss’ corporate office.
 
investigated further and found the font for “Carl Zeiss Jena” in the logo to be incorrect as well so I concluded they are high quality fakes which I have yet to verify with Zeiss’ corporate office.
Click to expand...

Zeiss should be able to tell you more (if they come back to you) - but I wonder if your 8x40 model was copied, as the 8x30s and 10x50s (and maybe 7x50s - not sure on this) were during the DDR era.

NB. I hope Rathaus is well - I enjoyed his enthusiasm for his binoculars and his joy in sharing his enjoyment of them was very evident.
 
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