Astrodon

I too would appreciate a reprint of your Light-Box article. Thanks, Charles

Sorry Guys, you may have been thinking of this light box illuminated by LEDs that I built some years ago. http://old.astrodon.com/oldsite/LearningCurve.html

Don

Dear Mr. Goldman,

I'm a filmmaker, in love with the Universe and an artist. I have done some astrophotography; however, your skills exceed mine. I am putting together some items for an art project I'm working on. They will be for sale and would very much like to use your images. I don't know what you prefer but would you be interested in a percentage of each item sold with one of your images on it? Thank you. Your pictures are amazing and inspiring. Sincerely, Natalie

Hi, Natalie, sorry for the delayed reply. I've sent my reply privately to your email.

Don: Concerning the Edge Lite LED panel you mention above. Why did you try the Edge Lite LED panel with the gird rather than the Electroluminenscent panel?

It seems the EL panels, from what I've seen, have no grid and should make a very even, continuous....and very flat light. As a photographer for many years I've built many light boxes as soft-light sources and it is difficult to get an even light with any 'point souce light'.

Kent Kirkley

Kent, I tried the grid panel and found it to be horribly non-uniform compared to the EL panel. I use the EL panel in my remote observatory. Don

Hello Don, With the soon to be release of Sbig Stx series of cameras, will you be manufacturing the required 65mm filters (LRGB Ha, ect.)? If so will they be available at the time of filter wheel release? Thanks...Jerald

I am discussing this with SBIG, so a final decision has not been made. Most of the community has moved away from guiding BEHIND filters due to its inherent difficulty. SBIG has commented that they will make a CFW for 50 mm square filters that will cover the internal guider in the STX, but will allow you to use an OAG with the remote guide head, such as my MonsterMOAG. In addition, 65mm square filters will be incredibly expensive. So, to me, it comes down to 3 things against 65 mm filters - 1. Degraded performance in guiding behind filters especiallyfor narrowband, 2. Increased cost, and 3. A better OAG alternative to guide with unfiltered light in front of the filters.

Hello Don,

I am considering purchasing the QSI 583wsg camera and I am planning to purchase your Astrodon Tru-Balance E Series LRGB Gen II Filter Set mounted in the new 31mm inserts. I image primarily from a heavily light polluted suburban enviroment and would also like to purchase your 3nm Ha, SII and OIII filter also mounted in 31mm inserts. Do you now have, or plan to soon release, these narrowband filters in the 31mm mountings?

****************They are all available for the same price. Just specify 31 mm insert when ordering the 1.25" filter.

I have been doing DSLR imaging for a few years and have used the Hutech IDAS LPS fillter. Do you have any recommendations on how to control the light pollution using the QSI camera and your LRGB filter set? I have the 2" filter and could use it in conjuction with your filters but, I am not certain how this would effect the performance of the system.

****************I would not use the LPS. You'll lose about 1/2 the light signal and will have to image at least twice as long. I find processing out color gradients in Photoshop with Russ Croman's GradXTerminator or using PixInsight's DBE is a better way too go. Imaging RGB in light pollution is tough nommatter what. My RGB filters do a good job to eliminate to dominant source of light pollution from sodium street lamps. However mercury lines will come right through into any blue or green filter. Don

Thank you,

Mike

Hi Don,

Thank you for your response. Would the 3nm filters require a longer exposure for a given S/N as compared to the 5nm filters? I am trying to determine which filter would be best for me considering the light pollution here. I would assume that the narrower filter would be better unless it requires a significantly longer exposure.

Mike

*******No, the peak transmittance (see our Narrowband FAQ page from the Narrowband page) is about the same between the 5 and 3 nm which means your signal remains strong, with lower background noise with the 3nm. I use 30 min exposures for both 3 and 5 nm narrowbands for this reason.

Thank you Don, Mike

Don will the ROAG guider that you used to make work with current automation software?

Ken, no it won't. The current automation software works with the TAKometer. Once you change the angle between the guider and the imaging sensor, you have to recalibrate the sky position angle. With rotators integrated into the automation program, the OAG/Guide Camera/Imaging camera act as a unit and you only calibrate once. The advancement of these programs with rotator integration made the ROAG obsolete. That's we we developed the MOAG and MonsterMOAGs. Don