Jump to content

Banner.jpg.b89429c566825f6ab32bcafbada449c9.jpg

All Sky Camera Revisited


Gina

Recommended Posts

Not too bad - some star elongation near the edge.  I get the impression that this lens is not as good as the first one but I could be wrong.  I'll have to check previous images.

Link to comment
Share on other sites

No the lens is uncovered.  The colour image was taken with the old lens and ASI 185MC camera last August with the 3" acrylic dome on.  That was before a severe storm ripped it off the observatory roof.

Link to comment
Share on other sites

I guess there a vanishingly small possibility that distortion in the dome corrected the distortion in the lens...  No, not so, I tried the lens without dome and it was perfect.  I feel gutted!  I don't know why the mast fell and it was sheer bad luck that the lens caught the corner of a paving stone.  Guess I shall just have to put up with less than perfection!  I guess I could ask for a replacement lens but there's no guarantee that another will be any better and could be worse.

Link to comment
Share on other sites

No guarantee they actually have another one to give you, either.  Can't help to contact them to say the lens has distortion that wasn't present in your earlier one though.  They might be able to replace it.

James

  • Like 1
Link to comment
Share on other sites

Actually, having had a quick look at their site it appears they have more in stock.  Looks like there's a 1.4mm and a 1.8mm version.  Have you definitely got the right one?

James

Link to comment
Share on other sites

Yes, it's 1.4mm according to the label and it gives the full sky view. So yes, certainly seems the right one.

Edited by Gina
Link to comment
Share on other sites

I suppose I could wait and see what it's like with the colour version of the camera (ASI 178MC) which is on order.  The dome might make a slight difference.  I've been trying to think if there is anything that could cause the elongated stars other than a faulty lens.

Edited by Gina
Link to comment
Share on other sites

The Dew Control 1.55mm All Sky Camera Lens looks very similar to the Arecont version and also Modern Astronomy seem to sell a similar one at a similar price.  I reckon that would give me sufficient coverage if I can't get any joy with the Fujinon lens and the fact that it has a focus facility is a bonus.

 

 

Edited by Gina
Link to comment
Share on other sites

It's 1/1.8" ASI 178MM at present 178MC in future - 5.992mm image height.  In view of the trees and rising ground to the NW I don't need views down to the horizontal all the way round.  The Fujinon 1.4mm lens gives 185 degrees and the full image circle is covered by the 178 camera sensor.  This covers not only the sky but some of the ground around too (quite nice in daytime).

I would prefer to buy from Bern at Modern Astronomy as I've bought there many times before and the service is excellent.  The lens is a pound cheaper than Dew Control too.

Edited by Gina
Link to comment
Share on other sites

Currently continuing to print parts for the ASC.  I'll give lenses more thought over the weekend but I think I shall have to send that faulty Fujinon back.

Link to comment
Share on other sites

The more I think about it the more I like the idea of the 1.55mm f2 lens from Bern.  It seems to give excellent resolution and no oblong stars.  It's also smaller than the Fujinon making for a smaller overall rig.

Link to comment
Share on other sites

On 08/03/2019 at 17:59, Gina said:

Currently continuing to print parts for the ASC.

That might be alright if only I could get the dimensions right... :eek:

Link to comment
Share on other sites

I have applied for return of that Fujinon 1.4mm lens and have ordered the 1.55mm lens from Bern at Modern Astronomy.  Several parts printed successfully.

  • Like 1
Link to comment
Share on other sites

Having printed enough parts to hold the camera, TEC and waterblock together, I set up to see how cold I could get the camera with the thermal insulation and all thermal parts in good contact with thermal grease (just light pressure).  More trouble - no Peltier TEC current and no cooling :eek:  Took it all apart again and checked volts across TEC - power was getting that far but no current.  All I can think of is that an internal connection or one of the elements has gone open-circuit. 

Link to comment
Share on other sites

The only thing I seem to be having much joy with lately is arts and crafts - paper craft particularly!  At W.I. Thursday evening we had a craft session making beads and hence bracelets or necklaces from rolled up bits of coloured paper and PVA glue.  I made a necklace and won first place in the competition.  I was flabbergasted.

  • Haha 2
Link to comment
Share on other sites

Maybe I should stick to doing things with my hands, though they're not as good as they were.  I do seem to be having a problem just lately in getting my brain round the more complicated things.  I'm getting worried that my age is catching up with me and now I'm being serious.  I tend to make fun of these things and not take myself too seriously but I'm definitely not as clear headed as I was.

Link to comment
Share on other sites

Nah, keep on as normal, otherwise you're just giving in..... 

These days, I find I may need to re-think some things through a few times, but half the fun is getting the right result in the end. Whether that be something I've designed & printed or some electronic system(s) I happen to be re-visiting e.g. currently fixing up an old Maplin 5600 synthesizer I built years ago, but was left languishing in an attic, so needs a little TLC, but some of the original components (ic's) are no longer available, so have to make do with some alternatives and adjust circuits to suit....

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.