TAKAHASHI EXTENDER-ED 1.5X - Forums

I recently received my TAK TSA-120 after waiting for it forever 😊. I am pretty stoked and was looking at reducer/extender options. Has anyone had any experience with the TAK ED 1.5 extender for imaging (smaller galaxies, planets, lunar, etc)? Even though it settles as F11 with 1350mm FL; as long as optics are sharp and not terrible at the edges, I would imagine it could potentially work with slightly longer exposure on targets requiring longer FLs (in broadband).

In general also, what is people’s sense on how it would compare with Televue powermate. For planets especially, I don’t know how much image quality boost will be seen with the TAK extender vs powermate Barlow. Price for extender is quite a lot and I already own powermate 2.5x.

thanks in advance for sharing.

Hello Kapil,

Though I do not personally have experience with the TSA-120 and these devices I was fortunate enough to speak with both Takahashi America as well as Al Nager of Tele Vue about your situation. Their positions echo my own feelings about these devices and their own inherent strengths.

As you mentioned, the 1.5x extender from Takahashi would offer some improved edge correction over your typical Barlow, and with the relative low extension factor, it would be well suited to imaging some smaller targets, like galaxies and planetary nebula. It might be less than ideal for planetary imaging. I was able to acquire a spot diagram for the 1.5 extender on your telescope. I also discovered that the extender could be used in combination with the field flattener, should you want an even better corrected field!

For planetary imaging your Tele Vue Powermate would be a better solution, though it would probably be a bit much for imaging galaxies, at F18.75. This Powermate's relative insensitivity to focal position compared to amplification power, combined with known quality optics, and the fact that you already own it make for a great choice for higher power imaging. There are other variables that come into play such as camera pixel size, as well as seeing conditions, however when comparing the 1.5x extender and 2.5x power mate, these are the strengths that stand out and each item has their own use.

I hope that this helps some!

Matt