The 67 is available, in fact I printed 4 specimens, but I would need to know the filter thread size of your 35mm lens to be able to print one for that lens. I've never heard of anyone using a mask for such short focal length but I'm sure that is because no one has been making them with fine enough slits.
Based on my tests I believe that a mask with 0.9mm slits would work on a bright star with that lens. If that fails I can go to extremes an print one with 0.5 slits - the limit of my printer.
Of course, sorry for not including that. They are both 67mm threads.
Josh
I guess a clear aperture of 50mm should be sufficient for the 35mm lens.
Is that ok with you? I don't want to compromise the mechanical integrity by making the slits longer than necessary.
No problem if you are prepared to wait in the queue a few days as I already promised someone a mask for a 5" refractor as well as Joshua's 67 with narrow slits.
I will need the size of the inside diameter of the dew shield measured quite accurately for a good fit if you decide to go ahead with it.
Hi Stefan I was wondering if you could make one to fit my ED/80 please
Hi Jen,
No problem, just give me an accurate (to better than a quarter of a mm) measurement of the inside diameter of the dew cap and a few days to get it done.
Hi Stefan,
I hope you won't mind my adding a positive feedback here. The mask you made for my ED127 arrived today and I'm more than pleased with it.
The things I find particularly pleasing include (in no particular order):
1. The frame and lip around the mask itself - this ensures the mask sits straight and is well seated in the dewshield;
2. Size - having specified 147.25mm as the ID of the dewshield, this mask fits perfectly - a nice positive fit without being tight or heaven forbid, too,loose;
3. Materials - I've had masks made in Oz that have been very brittle - fracturing or even shattering if dropped. This looks to be made of materials that will tolerate a drop or two;
4. Overall appearance - let's face it, the red lip is just plain sexy. What can I say??
Jen,
No it's not acrylic, it is ABS the same plastic that Lego blocks and many injection moulded toys are made of. It does not break if you bend it and it can take quite a bit of rough treatment - even though it may feel a bit flimsy, it retains its shape quite well.
as you can see its through a kitchen window
canon EOS 60d 18-135mm lens
this image was at 135mm
it works at 18mm not as good but still highly usable
My view the .9mm pitch is perfect as it lets more light through for dimmer objects. the other mask worked but hard to see light
oh PS this was a street light about 1.5km's away
