Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Good Quarks vs Bad?

  • Please log in to reply
8 replies to this topic

#1 cloudswimmer

cloudswimmer

    Vostok 1

  • -----
  • topic starter
  • Posts: 138
  • Joined: 09 Nov 2018

Posted 23 February 2021 - 11:50 AM

Hi, I’m considering a Quark Chromosphere for my TV-85 and SW ED100/900, and hear of the variation in copies .. which even Daystar on the phone admitted, so what do I look for after getting one to tell if it’s a keeper or a dud? Thanks


  • blakestree likes this

#2 briansalomon1

briansalomon1

    Ranger 4

  • *****
  • Posts: 336
  • Joined: 21 Jul 2018
  • Loc: Oxnard CA

Posted 23 February 2021 - 02:38 PM

I'd suggest starting off by inspecting it like you'd inspect a regular eyepiece, in good light take look at the glass surfaces. Of course there shouldn't be any scratches and the surfaces should be uniform and smooth.

 

Most images you see are digitally processed and will be sharper and show more detail than you will see visually.

 

Here is an image I think represents what I typically see visually with my quark. 

 

https://www.google.c...=JD8aKMEaxb07sM

 

Quarks are sold as an entry level H-alpha system and Daystar applies a "general" specification of how far it will tune above and below the H-alpha wavelength but they don't apply a detailed specification and don't try to misrepresent typical quark performance. In my opinion quarks are a bargain.


  • gustavo_sanchez and blakestree like this

#3 cloudswimmer

cloudswimmer

    Vostok 1

  • -----
  • topic starter
  • Posts: 138
  • Joined: 09 Nov 2018

Posted 23 February 2021 - 03:39 PM

Hi Brian, nice image!, did you shoot that? I have two scopes I’d like to try this on .. a Televue TV-85 and a Skywatcher ED100/900, being a Televue eyepiece user yourself what would you recommend eyepiece wise for a Quark .. 32mm Plossl perhaps? Thanks for the help!

I'd suggest starting off by inspecting it like you'd inspect a regular eyepiece, in good light take look at the glass surfaces. Of course there shouldn't be any scratches and the surfaces should be uniform and smooth.

 

Most images you see are digitally processed and will be sharper and show more detail than you will see visually.

 

Here is an image I think represents what I typically see visually with my quark. 

 

https://www.google.c...=JD8aKMEaxb07sM

 

Quarks are sold as an entry level H-alpha system and Daystar applies a "general" specification of how far it will tune above and below the H-alpha wavelength but they don't apply a detailed specification and don't try to misrepresent typical quark performance. In my opinion quarks are a bargain.



#4 briansalomon1

briansalomon1

    Ranger 4

  • *****
  • Posts: 336
  • Joined: 21 Jul 2018
  • Loc: Oxnard CA

Posted 23 February 2021 - 08:48 PM

It isn't my picture, I've always been just a visual guy but my mom really wanted to know what I could see with my telescope and she's not local so I've taken a few just send to her but not that one.

 

Technically, a good achromat is theoretically a slightly better performer than an APO for H-alpha but I think you will find both scopes work well.

 

The TV85 won't need an ERF but for extended use (especially tracking) you should probably get one for the Skywatcher.

 

Plossls do work better for H-alpha. Unless you start using a binoviewer the 32mm is probably longer than you want.

 

If you plug in the numbers here    https://skyandtelesc...ope-calculator/.    you can get a good idea which eyepieces you'd want. The Sun is 0.5 Deg wide so ending up with 0.75 deg or so would be ideal for low power.


Edited by briansalomon1, 23 February 2021 - 08:49 PM.


#5 MalVeauX

MalVeauX

    Cosmos

  • *****
  • Posts: 8,608
  • Joined: 25 Feb 2016
  • Loc: Florida

Posted 23 February 2021 - 09:19 PM

Hi, I’m considering a Quark Chromosphere for my TV-85 and SW ED100/900, and hear of the variation in copies .. which even Daystar on the phone admitted, so what do I look for after getting one to tell if it’s a keeper or a dud? Thanks

Ideally, you'd want to check it's overall uniformity once it's on-band and that you're confident it's as on-band as can be. You should be able to tune into the red and blue wings. If you cannot do that and you're forced to be in one or the other to be on-band, I wouldn't keep it. If the uniformity is messy, some areas brighter than others, on band and off band in the same FOV, etc, then I wouldn't keep it. Your 102mm F9 is a good scope for this use. Ideally you want to tune on a feature that is definitely chromosphere (ie, not a sunspot), such as plage, mottling and filaments as they will be very bright and dark (respectively) when on-band.

 

Very best,



#6 betacygni

betacygni

    Explorer 1

  • *****
  • Posts: 62
  • Joined: 06 Feb 2011

Posted 23 February 2021 - 09:29 PM

I ran into a similar issue a while back (might have seen my thread) and essentially I came to the conclusion that it’s a good one if there are no obvious visual defects (view is uniform, aren’t sweet spots that are better, etc). The link above is indeed pretty much what I see visually. H-alpha is one of those things that the longer you look the more you start to see. And don’t be afraid to adjust the tuning. I found on my unit the prominences become much more visible if I adjust the dial all the way to the left, though of course at some surface detail cost.

As for eyepieces neither of your scopes will be able to get a full disc view stock (it takes a focal length of less than 450mm), 32mm plossl is indeed where I would start. So far with my setup I’ve found 25mm or longer to be best, but I haven’t used aperture over my 60mm yet, so others might be able to speak better on that.

I’ve tested a few plossls and so far I really like the baader 32mm. It beat out others in terms in seeing detail, and I think partly because the lens is so far recessed into the body, it helps to shield it from ambient daylight. Winged eye cup also helps with that.

Binoviewers is really where it is at though, massive increase in what you can see, and viewing comfort. Doesn’t require anything fancy to come to focus either, since quark has a built in Barlow.

Edited by betacygni, 23 February 2021 - 09:33 PM.

  • briansalomon1 likes this

#7 briansalomon1

briansalomon1

    Ranger 4

  • *****
  • Posts: 336
  • Joined: 21 Jul 2018
  • Loc: Oxnard CA

Posted 24 February 2021 - 09:59 AM

As for eyepieces neither of your scopes will be able to get a full disc view stock (it takes a focal length of less than 450mm), 32mm plossl is indeed where I would start. So far with my setup I’ve found 25mm or longer to be best, but I haven’t used aperture over my 60mm yet, so others might be able to speak better on that.
 

Thanks for catching that - I'd completely forgotten about the built in 4.3 barlow in quark.....

 

My quark manual says you can get a full solar disk at ~450mm focal length but they're very conservative, (the eyepiece affects this) I'm getting a nice full disk with NP101 at 540mm.

 

I dug up this formula for calculating TFOV: Divide the focal length of the telescope by the focal length of the eyepiece. This will give you the magnification (power). Divide the apparent field of view of the eyepiece by the magnification. This will give you the true field of view.

 

NP101 540mm focal length/32mm eyepiece = 16.9X magnification and with the 4.3 barlow it's 72.6X magnification.    With the TV plossl at 50 deg AFOV it's 50/72.6 = 0.68 deg true field of view and this jibes with what I see through my telescope.

 

TV85 600mm focal length/32mm eyepiece = 18.8X magnification and with the 4.3 barlow it's 80.6X.   With TV plossl 50/80.6 = 0.62 deg so the 0.5 deg solar disk should fit and give a nice image.

 

SW ED100/900 900mm focal length/32mm eyepiece = 28X and with 4.3 barlow is 120.9X   so 50/121 = 0.41 deg and won't give a full disk.

SW ED 100/900 900mm focal length/40mm eyepiece = 22.5 X and with 4.3 barlow is 96.8X   so 43/90 = 0.44 deg and won't give a full disk.


Edited by briansalomon1, 24 February 2021 - 11:00 AM.


#8 blakestree

blakestree

    Vostok 1

  • *****
  • Posts: 159
  • Joined: 26 Aug 2011
  • Loc: Savannah, GA

Posted 24 February 2021 - 10:15 AM

Personally, I would start with a 25mm, if your seeing would allow the magnification.



#9 Spikey131

Spikey131

    Surveyor 1

  • *****
  • Posts: 1,983
  • Joined: 07 Feb 2017

Posted 24 February 2021 - 10:34 AM

With a 900mm focal length and the 4x Barlow in the Quark, you will definitely want a 32 Plossl.

If you buy the Quark new, Daystar will work with you if you are not satisfied. At least that has been the feedback here on CN.
  • marktownley likes this


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics