Instruction: Given a question and the related document, and generate the answer to the question based on the information provided in the document.

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Question: Just received the flash last week.  First fire needs 20min ' warn up'?  Same problem when flash is not used for few days.
Document: This Sunpak Flash was just what I needed to complete my lighting needs for picture taking. And as for the cost I could not have found one of the quality I give it a five star.
As with all Sunpac products I have purchased and used the quality of the item is very good. It just dosnt put out much more light than the built in flash.
This flash has problems with the new Canon EOS M, it does not always work  in TTL mode, the flash it will fire in manual mode and wash out the image. it works fine on my Canon XTi and 60D.
Got this for my son. He said he likes it but needs an adapter for it to fit his camera
when I received it, I saw that I had overlooked the fact the Sunpak flash would not work with my Olympus e-420. Can I return it?Do you have a flash unit that is adaptable to the e420?
Most people misunderstand how flash should be used and expect too much. This flash isn't meant to light a large group, a big hall or reach 50 feet. It's best within 10-12 feet to fill shadows on faces, etc. At [$] you can't go wrong and if it takes a hit and dies, it's cheap to replace.
Simple fix. Last minor gripe would be no swivel, but the flash doesn't stick up enough for this to be as effective as a larger/taller flash anyway. Lastly, I wish it worked with Pocket Wizards but alas, it doesn't. Bummer.Other thoughts:I use three of these all the time on a G12, 5D, 30D, 40D and 60D.
I love this flash! I have had it for about 2 months. My most recent camera is a used Canon 5D, which has no built-in flash unit. After careful investigation, I decided to buy this external flash custom-tailored to Canon EOS cameras, but costing a fraction of a Canon flash. It is more powerful than built-ins, but less so than the huge units which tower on the top of the professional's cameras.
the only problem is that it doesn't have a focus assist light, so if its too dark, its up to you.. really this is problem more with canon not focusing in the dark very well..  but the lens is nice and compact for sure..
The Sunpak RD2000 comes in a small box, but when you open the box, you may be surprised at the even smaller size of the Sunpak RD2000. Yet this is a very good flash choice for small cameras (with a few caveats).I received this flash as a gift, and as soon as I opened the box today and installed 2 AA batteries, it was ready to go.
Answer: 20 minutes? Something is wrong.  It takes no more than 10 seconds for the first fire even when the alkaline battery is halfway used.