A Demonstration of Accurate Wide-field V-band Photometry Using a Consumer-grade DSLR Camera

TL;DR

This paper demonstrates that consumer-grade DSLR cameras can perform accurate wide-field V-band photometry for bright variable stars, offering a cost-effective alternative to traditional equipment.

Contribution

The study develops and tests a color-based transformation method to achieve high-precision photometry using DSLR cameras, showing their viability for variable star research.

Findings

DSLR green channel photometry agrees well with VT photometry.

A reliable color transformation to Johnson V band was established.

DSLRs can be used for accurate wide-field photometry with minimal investment.

Abstract

The authors examined the suitability of using a Digital Single Lens Reflex (DSLR) camera for stellar photometry and, in particular, investigated wide field exposures made with minimal equipment for analysis of bright variable stars. A magnitude-limited sample of stars was evaluated exhibiting a wide range of (B-V) colors taken from four fields between Cygnus and Draco. Experiments comparing green channel DSLR photometry with VT photometry of the Tycho 2 catalogue showed very good agreement. Encouraged by the results of these comparisons, a method for performing color-based transformations to the more widely used Johnson V filter band was developed and tested. This method is similar to that recommended for Tycho 2 VT data. The experimental evaluation of the proposed method led to recommendations concerning the feasibility of high precision DSLR photometry for certain types of variable star projects. Most importantly, we have demonstrated that DSLR cameras can be used as accurate, wide field photometers with only a minimal investment of funds and time.