Photometry with VPHOT
VPhot is an AAVSO membership service that lets you do photometry on astronomical CCD images online, designed primarily for robotic telescopes. Images do not have to be downloaded to your local computer, all work is done in the browser. This means that there is no software installation or maintainance, operating system is irrelevant, you can work from anywhere, and, if you want to, sharing images is easy.
PLEASE NOTE: YOU NEED TO BE AN AAVSO MEMBER IN ORDER TO USE VPhot.

How to use VPHOT
VPHOT is an online photometry application for AAVSO members, and is seamlessly integrated with the iTelescope systems. If you choose to send your images to the VPHOT server they will automatically be calibrated, plate solved and ready for photometric analysis in VPHOT online. Note that it might take 10-30 minutes before the images appear in VPHOT depending on network traffic, server load etc.
In order to use VPHOT you have to be an AAVSO member. You start by going to the AAVSO web site athttp://www.aavso.org/ and log on to their web site with you AAVSO user name. Then you enter the VPHOT server via the link at the bottom of this page:
http://www.aavso.org/vphot
Before you can see your images in VPHOT you need to tell the system your iTelescope.Net user name so that it can correctly identify your images as they come in from the GRAS telescopes. To do this, you click the 'Admin' link in the top menu of VPHOT and then click 'Image Transfer (Connect Accounts)'. Follow the instructions on that page. You only have to do this once.
Each page in VPHOT has a help link that explains the details of that particular page. You can also view the excellent video tutorials below.
Note that some features have changed and new ones added since these videos were made, though the main features are the same.
These video tutorials have been produced by Ken Mogul.
- Introduction to VPHOT
- Available Images List
- Single Image Analysis
- Target Verification
- Changing the Centroid
- Reporting Data
- Sequences
- Time Series and Stacking
Please direct questions and comments to the VPHOT forum.




