Hi all,
Last September I have teseted my new development - a Universal CaK corrector.
Here the results how does it work in such a difficult conditions - in a very fast 100mm F/5 achromat.
Without a corrector I were not able to detect even sign of granulation. Spots, bright regions and
some bright "creeks" without details in them. Also, no solid focus - always feel to refocus again and again.
With the corrector in place the focus is like a sharp edge. Smallest move of the focuser and no longer focus,
no sharp edge details on the screen.
Photos were taken in a slightly different seeing. You can see what the resolution can a fast achromat 100mm F/5
can deliever at 393nm if it is corrected for spherical aberration at this wave length.
Note that SA at 393nm in a 100mm F/5 achromat is about 2,7 Lambda !!! In a 150mm F/5 is is even higher - 4 Lambda!
In a 150mm this corrector work similarly good, just need to be somewhat close to the telescope objective.
If enough peoples will be interested, we can make a small batch of such correctors. The price is about $800 - 900
depends of how many samples will be ordered in a batch.
Click on the images to see them at a full resolution.
Valery
Ca-K correcting lens test results.
- Valery
- Way More Fun to Share It!!
- Posts: 4059
- Joined: Sun Nov 18, 2012 3:13 pm
- Has thanked: 156 times
- Been thanked: 893 times
Ca-K correcting lens test results.
Last edited by Valery on Thu Dec 03, 2015 10:09 am, edited 1 time in total.
"Solar H alpha activity is the most dynamic and compelling thing you can see in a telescope, so spend accordingly." (c) Bob Yoesle.
Largest full size 185 - 356mm Dielectric Energy Rejection Filters (D-ERF) by ARIES Instruments.
Largest full size 185 - 356mm Dielectric Energy Rejection Filters (D-ERF) by ARIES Instruments.
- marktownley
- Librarian
- Posts: 42550
- Joined: Tue Oct 18, 2011 5:27 pm
- Location: Brierley Hills, UK
- Has thanked: 20819 times
- Been thanked: 10489 times
- Contact:
Re: Cak correcting lens test results.
Nice results! All my scopes are running at f10, would it improve things there? What diameter is the lens?
http://brierleyhillsolar.blogspot.co.uk/
Solar images, a collection of all the most up to date live solar data on the web, imaging & processing tutorials - please take a look!
- Valery
- Way More Fun to Share It!!
- Posts: 4059
- Joined: Sun Nov 18, 2012 3:13 pm
- Has thanked: 156 times
- Been thanked: 893 times
Re: Cak correcting lens test results.
I believe that such a correcting lens is useful for larger telescopes with relatively fast and very fast objectives.marktownley wrote:Nice results! All my scopes are running at f10, would it improve things there? What diameter is the lens?
A 40mm F/10 really don't need corrector which costs 20x as much.
The entry size for solar CaK telescopes I consider 100mm F/5. Of course, an 80mm F/5 - F/7 will work too, but again
the corrector is too expensive to use it there.
The next is 100mm F/8-10 and all scopes larger than 100mm in aperture.
Valery
"Solar H alpha activity is the most dynamic and compelling thing you can see in a telescope, so spend accordingly." (c) Bob Yoesle.
Largest full size 185 - 356mm Dielectric Energy Rejection Filters (D-ERF) by ARIES Instruments.
Largest full size 185 - 356mm Dielectric Energy Rejection Filters (D-ERF) by ARIES Instruments.
-
- Way More Fun to Share It!!
- Posts: 12900
- Joined: Wed Oct 19, 2011 10:02 am
- Been thanked: 171 times