if you're considering modifying your dslr or mirrorless camera for astrophotography you usually
have a few different choices and the goal with all of these mods as we call them is to let in more
light in the deep reds of the visible spectrum the issue with stock cameras is that they have
a fairly aggressive ir cut filter that rolls off gradually in these deep reds and that gradual roll
off means that the h alpha emission line which is so important for capturing emission nebulae
is only passed at somewhere from around 20 to 50 transmission after modification you typically pass
that line at over 95 transmission and that makes it much easier to photograph these dim
emission nebulae like the heart and soul or the california nebula or the north america and pelican
and if you've looked into camera mods you may have seen terms like low pass filter full spectrum Ha
mod Baader mod and felt overwhelmed by all of the different choices here well this video will
clear up the actual physical differences of these different types of camera mods but also
go into their pros and cons and what to expect from each mod when it comes to real world results
under the night sky and to do this i'll be showing my results all taken on the same night
with these different cameras with the same askar 200 millimeter lens and i'll do some
head-to-head comparisons at the end to be clear this video is not going to go over how to modify
your camera yourself if you are interested in that you can find guides on the web but personally
i've never done it myself because i don't have a clean room and i don't really have any
experience or particular skills with small electronics so i've always sent my cameras out for
modification or bought them already modified and if you're interested in sending your camera out
to be modded or buying an already modded camera i can recommend astrogear.net i've had a long call
with the owner and he really knows his stuff i sent him this canon eos t7 dslr for modification
he did a batter mod on it i've been using it for months and the results have been great so
astrogear.net and my affiliate link is in the description so let's dive in to start with let
me just break down the anatomy of the filter stack in a typical stock dslr or mirrorless canon camera
after you open up the mirror light first hits the lpf1 filter which is an anti-aliasing filter it
also so what an anti-aliasing filter does is it blurs small detail a little bit the point
of this is to get rid of moire patterns but uh those don't really affect us in astrophotography
the lpf1 filter also is necessary if your camera has an auto dust cleaning function
that doesn't really matter to me i usually turn off the autodust cleaning function anyways because
if you're not careful with flat fielding that can be a problem anyways then behind the lpf1
filter is the lpf2 filter and this is the filter that needs to be removed in every kind of mod
because this is the one that's affecting the deep reds of the visible spectrum
and cutting off some of the ha and usually all of the s2 what i just went over lpf1 lpf2
being two different filters is true of canon for sony and nikon it's a little bit different
and often those filters are all glued together in a sandwiched filter style so that affects the
kinds of mods you would do a little bit but it's it's the basic same idea as as what you have with
canon that there's different sort of filters in a low-pass filter stack that do different things
and uh the one that you really have to remove is usually called the lpf2 because that's the one
that's limiting those reds if you just remove the lpf2 filter but retain the lpf1 filter
that's uh one of many mods that we might call an ha mod and it's one of the most popular because
it's usually the cheapest mod out there and there are a variety of mods that also combine removing
the lpf2 or the entire low-pass filter and then adding some kind of astro specific filter back
in internally and the most typical one you'll see is adding back an illuminance filter also known as
an astronomy-specific uv-ir cut filter and those are usually provided by the company Baader and the
Baader filter is so popular for modding that when it's used it's usually just called a Baader mod
and so that's what i'll call it in in this video in my case what i had done was i had the lpf one
and two removed and the bottom filter added in by astrogear.net and then another kind of popular
mod is the full spectrum mod where you remove the lpf1 and lpf2 filter and either replace them with
clear glass or don't replace them at all and just have a naked sensor so to review the the types are
lpf2 removal lpf1 retained a batter mod where lpf 1 and 2 have been removed and a Baader
luminance filter is added internally and then a full spectrum mod where everything's taken out
and i'll be comparing these three different kinds of camera mods lpf2 removed bottom mod and full
spectrum mod to a stock dslr and to my canon EOS Ra which is sort of a weird case of a camera that
you buy stock but it's already been pre-modified by canon and they charge a big premium for that
i won't dwell on the ra in this video though because you can just watch my full review of it
where i go into all of the the details of what the ra is all about including the ra is really
just for a point of comparison when we get to the end uh when i'm doing comparisons of all the
different types of mods so let's jump into each camera mod look at the results the pros and cons
and we'll start with this canon 60d which has had the lpf2 filter removed if you get this mod
done by astrogear.net it's the cheapest one they offer at 169 here's the resulting photo this is 18
photos at 30 seconds each stacked together and we can compare it here to the stock dslr on the north
american pelican nebulae and you can see that the colors are pretty different because when you
mod you're letting in all that hydrogen signal so on an emission nebula like this it really
helps firm up details even in the bright parts of the nebula like the cygnus wall region here
i'd say the biggest pro of this mod is that it's the cheapest it works quite well at letting in
more ha and you retain the lpf1 filter which gives some protection from the elements if you ever
open the camera up without a lens or telescope on it it does give the lpf1 filter does give those
small stars a little bit of a blur and we'll talk about that next and comparing this one to a 60d
that's been has the full spectrum meaning that both the whole entire low pass filter
assembly has been removed i replaced it with an astronomic l2 uvir block filter that's a clip in
and at first glance it might look nearly identical to the last mod but the removal of the lpf1 filter
means that if we look at the stars very closely you'll see that that lpf1 filter does blur small
detail and without that anti-aliasing effect we can split stars with the full spectrum camera
because the small details sharpen up a little bit this is a small enough difference that i'm
not sure if artistically i care because zoomed out like i say they look basically identical to my eye
but the real advantage of the full spectrum camera is that it's a bit more flexible
i could remove this astronomic l2 which i use for nighttime shooting and put in an ir pass filter on
front of a lens like like this Hoya r72 and do infrared photography during the day which i've
only done on a few occasions but it was really fun i want to do more of it and so that's a big pro
of the full spectrum is that it's more flexible the the downside is you'll likely pay a bit more
to get this added flexibility because you're buying different kinds of filters and things
so next let's compare these two that we've done to the Baader mod which is like full spectrum but
then they add a Baader luminance filter back in internally rather than having to use a clip in or
an external ir cut filter and this makes the mod a bit more expensive but let's see if it's worth it
over the extra cost of for instance just an lpf2 removal and interestingly the color rendering is
pretty different we still get plenty of signal but we don't get as overpowered by the reds
if we go back to the stock camera comparison you can see it's just a tad closer than with the other
two mods one thing i do wonder is if i used an astronomic l3 rather than an l2 if that might
be more similar to the Baader but anyways i i like this color rendering and it leads me into my last
comparison here which is the canon ra the stars will look bloated compared to the other cameras
because i've cropped down from full frame and the ra has significantly bigger pixels than these crop
sensor cameras but that's also why it's a brighter image than the others because of these bigger
pixels but if we can get past those differences i think it compares pretty well to the Baader mod so
let's bring them all back up now and look at some crops i'd say that the differences are
all pretty subtle with a few small adjustments in photoshop i could probably make all of these
look even more identical than they do here as another test though i did a daytime shootout
with a lamp set to 6000 kelvin which is pretty close to sunlight it's sort of a bluish white
and i first put all of the cameras onto full auto including auto white balance and took
snapshots and here's the results there and you can see with modified cameras auto white balance
is a pretty bad idea except with the Canon EOS Ra in which case it works fine because canon's
already done a white balance shift in the firmware so to even the score let's set a custom white
balance with a gray card for each camera before taking the snapshots and these are the results
so obviously much closer and it really is uh they can be used with a custom white balance
if you've enjoyed this video i'm gonna have a part two in this series on camera
mods one week from today where i'll be comparing a modded canon dslr to a modded
nikon dslr and we'll see if i'm so wowed by the nikon that i want to switch to the
dark side of the force well till then this has been Nico Carver nebulaphotos.com Clear Skies!