Sloan g/r/i/z Photometry: ASASSN-21gq

Image:
Object: ASASSN-21gq
DATE-OBS: 2021-04-27T22:58:40.3008
EXPTIME(Seconds): *B/*V/*R/*I/240g’2/300r’2/240i’2/300z’2
SUBFRMS: *B/*V/*R/*I/4g’2/5r’2/4i’2/5z’2
OBJCTRA: 19 15 51.69
OBJCTDEC: -07 12 42.3
Instrument:
Astrometry Catalog: ATLAS: Y, UCAC4: N, GAIAEDR3: N
Photometry Catalog: : UCAC4: N, APASS: N, ATLAS: Y
Johnson/Bessel: (B): +*.*, (V): +*.*, (R): +*.*, (I): +*.*
Sloan: g’2: +14.105, r2: +13.409, i’2: +13.140, z’2: +12.935
CCD: ATIK-383L+
FILTERS:
Sloan: u’2: N,g’2: Y,r’2: Y,i’2: Y,z’2: Y
Johnson/Bessel: U: N,B: N,V: N,R: N,I: N,
TELESCOPE: C11, 1623.0mm
PRiSMv10, Tycho8.0
Site:
ORIGIN: Cepheid Observatory, India, Vorion Scientific, India
SITELAT: +24:55:00:00
SITELONG:+75:33:58:99
Observers:
K.V
Measures:
S.M, B.K, V.A.
Remark:
Sky Clear, Full Moon
End

Sloan z’2

How much far! How much close! a C11 SCT is?

We examined a random star field near to galactic band using Exoplanet Blue Blocking filter (The spectrum of the Astrodon ExoPlanet-BB filter is shown Below). It blocks UV and blue light.  It starts transmitting light near 500 nm, corresponding to the shape of the conventional V-band filter and continues to transmit light into the near-infrared.

The purpose of using this filter was to achieve the best possible focus at red end. The 40 sub frames of 120 seconds were taken using PRiSMv10. The image stacked and photometrically calibrated using star catalog ATLAS and Tycho8.0. We achieved the best possible average magnitudes at V band (conversion) to +21.50

Image:
Object: Random Star Field
DATE-OBS: 2021-04-18T21:28:25
EXPTIME(Seconds): *B/*V/*R/*I/*g’2/*r’2/*i’2/*z’2/4800ExBB
SUBFRMS: *B/*V/*R/*I/*g’2/*r’2/*i’2/*z’2/40ExBB
OBJCTRA: 18 19 30.15
OBJCTDEC: +09 28 07.1
Instrument:
Astrometry Catalog: ATLAS: Y, UCAC4: N, GAIAEDR3: N
Photometry Catalog: : UCAC4: N, APASS: N, ATLAS: Y
Johnson/Bessel: (B): *.*, (V): *.*, (R): *.*, (I): *.*
Sloan: g’2: *.*, r2: *.*, i’2: *.*, z’2: *.*
CCD: ATIK-383L+
FILTERS:
Sloan: u’2: N,g’2: N,r’2: N,i’2: N,z’2: N, ExBB: Y
Johnson/Bessel: U: N,B: N,V: N,R: N,I: N,
TELESCOPE: C11, 1623.0mm
PRiSMv10, Tycho8.0
Site:
ORIGIN: Cepheid Observatory, India, Vorion Scientific, India
SITELAT: +24:55:00:00
SITELONG:+75:33:58:99
Observers:
K.V
Measures:
S.M, B.K, V.A.
Remark:
Sky Clear, 
End

Random Star Field (Star Spikes are artifact only to make image interesting)
Original FITS
Astrodon Exoplanet BB Filter

Sloan g/r/i/z Photometry: ASASSN-21fr

Image:
Object: ASASSN-21fr
DATE-OBS: 2021-04-15T22:39:47.7936
EXPTIME(Seconds): *B/*V/*R/*I/900g’2/900r’2/1050i’2/1680z’2
SUBFRMS: *B/*V/*R/*I/15g’2/15r’2/14i’2/14z’2
OBJCTRA: 18 36 21.85
OBJCTDEC: 37 32 56.40
Instrument:
Astrometry Catalog: ATLAS: Y, UCAC4: Y, GAIAEDR3: N
Photometry Catalog: : UCAC4: N, APASS: N, ATLAS: Y
Johnson/Bessel: (B): +*.*, (V): +*.*, (R): +*.*, (I): +*.*
Sloan: g’2: +14.815, r2: +15.174, i’2: +15.423, z’2: +15.634
CCD: ATIK-383L+
FILTERS:
Sloan: u’2: N,g’2: Y,r’2: Y,i’2: Y,z’2: Y
Johnson/Bessel: U: N,B: N,V: N,R: N,I: N,
TELESCOPE: C11, 1623.0mm
PRiSMv10, Tycho8.0
Site:
ORIGIN: Cepheid Observatory, India, Vorion Scientific, India
SITELAT: +24:55:00:00
SITELONG:+75:33:58:99
Observers:
K.V
Measures:
S.M, B.K, V.A.
Remark:
Sky Clear, http://www.astronomy.ohio-state.edu/asassn/transients.html
End

Sloan g’2

V/R/I Photometry: ASASSN-21fh

Image:
Object: ASASSN-21fh
DATE-OBS: 2021-04-12T23:08:38
EXPTIME: 600.00 (seconds)
SUBFRMS: 20I/20R/15V
OBJCTRA: 17 09 08.11
OBJCTDEC: -37 30 40.9
Instrument:
Catalog: APASS
Bessell (B): +*.*, Bessell (V): +8.84*
Bessell (R): +8.03, Bessell (I): +7.09
CCD: ATIK-383L+
FILTERS: V/R/I
TELESCOPE: C11, 1623.0mm
PRiSMv10, Tycho
Site:
ORIGIN: Cepheid Observatory, India, Vorion Scientific, India
SITELAT: +24:55:00:00
SITELONG:+75:33:58:99
Observers:
V.K.Agnihotri, B. Kumar, S. Mahawar, K.Vora
Remark:
Sky Clear. https://www.aavso.org/aavso-alert-notice-740
End

Electronic Telegram No. 4955
Central Bureau for Astronomical Telegrams
Mailing address: Hoffman Lab 209; Harvard University;
20 Oxford St.; Cambridge, MA 02138; U.S.A.
e-mail: cbatiau at eps.harvard.edu (alternate cbat at iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network

V1710 SCORPII = NOVA SCORPII 2021 = PNV J17091000-3730500
Paul Camilleri, Katherine, Northern Territory, Australia, reports his
discovery of an apparent nova (mag 9.5) on three 5-s exposures taken on Apr.
12.7625 UT with a Nikon D3200 digital SLR camera (+ 85-mm-f.l. f/2 lens),
noting the variable to have an orange color; the approximate position was
given as R.A. = 17h09m50s, -37d30’50” (equinox J2000.0). The variable was
given the provisional designation PNV J17091000-3730500 automatically when it
was posted to the Central Bureau’s TOCP webpage. R. Fidrich, Budapest,
Hungary, provides position end figures 08s.11, 40″.9 measured on a B-band CCD
image obtained on Apr. 12.814 with an iTelescope 0.50-m f/6.8 reflector
located at Siding Spring, NSW, Australia. F. Kugel, Banon, France, measured
position end figures 08s.32, 42″.6 from three stacked 30-s CCD images taken
with a 195-mm-f.l. f/2.8 lens on Apr. 13.12. A. Pearce, Nedlands, W.
Australia, provides position end figures 08s.10, 40″.9 from a CCD image
obtained remotely on Apr. 13.632 with a 0.43-m f/6.8 reflector located at
Siding Spring (reference stars from the Gaia DR2 catalogue).
Additional digital-image magnitudes (unfiltered unless noted otherwise)
that have been reported for PNV J17091000-3730500: Apr. 11.395 UT, [16.8
(All-Sky Automated Survey for Supernovae; communicated by P. Schmeer,
Saarbruecken-Bischmisheim, Germany); 11.682, [13.8 (R. McNaught,
Coonabarabran, NSW, Australia; 59-s exposure with Canon 6D camera +
135-mm-f.l. f/2.8 lens); 11.758, [12 (Camilleri); 11.794, [13.5 (McNaught);
12.168, g = 11.1 (ASAS-SN; independent discovery reported by Schmeer; position
end figures 08s.11, 40″.4); 12.408, g = 10.4 (ASAS-SN; Schmeer); 12.55, 9.5
(R. Kaufman, Bright, Vic., Australia; green channel approximating V band,
Canon 800D camera + 200-mm-f.l. lens; image posted via the following URL
https://tinyurl.com/4t5akzyy); 12.583, 9.6 (McNaught); 12.687, 9.5 (McNaught);
12.796, 9.4 (McNaught); 12.814, B = 10.64 (Fidrich; the variable was very red,
with B-V being at least +1.5); 12.955, R = 8.03 (V. Agnihotri, Kota,
Rajasthan, India; communicated via E. O. Waagen, AAVSO); 12.965, I = 7.09
(Agnihotri); 12.972, V = 8.84 (Agnihotri); 13.12, 8.9 (Kugel); 13.372, B =
9.71 (J. Backman, Lappeenranta, Finland; via Waagen); 13.422, B = 10.05 (J.-F.
Hambsch, Mol, Belgium; via Waagen); 13.423, I = 6.74 (Hambsch); 13.424, V =
8.69 (Hambsch); 13.632, V = 8.53 (Pearce); 13.633, B = 10.32 (Pearce); 13.634,
I = 6.58 (Pearce); 13.787, 8.5 (F. Romanov, Yuzhno-Morskoy, Nakhodka, Russia;
from five stacked 5-s exposures taken with a Canon EOS 60D camera +
135-mm-f.l. f/5.6 lens at ISO 6400 with a hazy sky; image posted at website
URL https://www.flickr.com/photos/filipp-romanov/51114244018).
Visual magnitude estimates for PNV J17091000-3730500: Apr. 13.068 UT,
8.8 (A. Amorim, Florianopolis, Brazil; via Waagen); 13.128, 8.9 (L. Araujo,
Pelotas, Brazil; via Waagen); 13.342, 8.7 (Amorim); 13.715, 8.8 (C. Wyatt,
Walcha, NSW, Australia; via Waagen); 13.732, 8.8 (Pearce).
Waagen also informs the Bureau that Joshi et al. have reported that their
spectroscopy obtained on Apr. 12.916 UT with the Mt. Abu PRL 1.2-m telescope
(range 440-900 nm, resolutions about 500 and 2000) show this to be an “Fe II”-
type of classical nova caught early in its outburst, with H-alpha, H-beta, Fe
II, and O I lines showing P-Cyg profiles on a red continuum (details are given
at website URL https://www.astronomerstelegram.org/?read=14544).
E. Kazarovets informs the Central Bureau that the permanent GCVS
designation V1710 Sco has been given to this nova.

NOTE: These ‘Central Bureau Electronic Telegrams’ are sometimes
superseded by text appearing later in the printed IAU Circulars.

                     (C) Copyright 2021 CBAT

2021 April 14 (CBET 4955) Daniel W. E. Green

PNV J17581670-2914490

Image:
Object: PNV J17581670-2914490
DATE-OBS: 2021-04-09T22:44:01.89
EXPTIME: 600.00 (seconds)
SUBFRMS: 20I/20R/20V
OBJCTRA: 17 58 16.70
OBJCTDEC: -29 14 49.00
Instrument:
Catalog: ATLAS
Bessell (B): +*.*, Bessell (V): +8.87*
Bessell (R): +7.92, Bessell (I): +7.07
CCD: ATIK-383L+
FILTERS: V/R/I
TELESCOPE: C11, 1623.0mm
PRiSMv10, Tycho
Site:
ORIGIN: Cepheid Observatory, India, Vorion Scientific, India
SITELAT: +24:55:00:00
SITELONG:+75:33:58:99
Observers:
V.K.Agnihotri, B. Kumar, S. Mahawar, K.Vora, K Arora
Remark:
Sky Clear.
End

VRI Image

Photometry: C/2021 R4 ATLAS

Image:
Object: C/2020 R4 ATLAS
DATE-OBS: 2021-04-02T22:59:39.4896
EXPTIME: 2040.00 (seconds)
SUBFRMS: 34
OBJCTRA: 19 42 07.77
OBJCTDEC: +00 00 51.90
Instrument:
Catalog: UCAC4
Bessell (B): +*.*, Bessell (V): +*.*
Bessell (R): +14.3, Bessell (I): +*.*
CCD: ATIK-383L+
FILTERS: R
TELESCOPE: C11, 1623.0mm
PRiSMv10, Tycho
Site:
ORIGIN: Cepheid Observatory, India, Vorion Scientific, India
SITELAT: +24:55:00:00
SITELONG:+75:33:58:99
Observers:
V.K.Agnihotri, B. Kumar, S. Mahawar, K.Vora
Remark:
Sky Clear.
End

SN2021hiz/IC3322A

Image:
Object: SN2021hiz/IC3322A
DATE-OBS: 2021-04-04T17:28:28.060
EXPTIME: 4950.00 (seconds)
SUBFRMS: 55
OBJCTRA: 12 25 41.67
OBJCTDEC: +07 13 42.3
Instrument:
Catalog: ATLAS
Bessell (B): +*.*, Bessell (V): +*.*
Bessell (R): +14.0, Bessell (I): +*.*
CCD: ATIK-383L+
FILTERS: R
TELESCOPE: C11, 1623.0mm
PRiSMv10, Tycho
Site:
ORIGIN: Cepheid Observatory, India, Vorion Scientific, India
SITELAT: +24:55:00:00
SITELONG:+75:33:58:99
Observers:
V.K.Agnihotri, B. Kumar, S. Mahawar, K.Vora
Remark:
Sky Clear, Star marked in blue box are ATLAS catalog data.
End

SN2021hpr/NGC3147

Image:
Object: SN2021hpr/NGC3147
DATE-OBS: 2021-04-04T16:44:14.22
EXPTIME: 1440.00 (seconds)
SUBFRMS: 16
OBJCTRA: 10 16 38.62
OBJCTDEC: +73 24 01.80
Instrument:
Catalog: ATLAS
Bessell (B): +*.*, Bessell (V): +*.*
Bessell (R): +15.7, Bessell (I): +*.*
CCD: ATIK-383L+
FILTERS: R
TELESCOPE: C11, 1623.0mm
PRiSMv10, Tycho
Site:
ORIGIN: Cepheid Observatory, India, Vorion Scientific, India
SITELAT: +24:55:00:00
SITELONG:+75:33:58:99
Observers:
V.K.Agnihotri, B. Kumar, S. Mahawar, K.Vora
Remark:
Sky Clear, Star marked in blue box are ATLAS catalog data.
End

C/2020 R4 ATLAS

Image:
Object: C/2020 R4 ATLAS
DATE-OBS: 2021-04-02T22:59:39.4896
EXPTIME: 2040.00 (seconds)
SUBFRMS: 34
OBJCTRA: 19 42 07.77
OBJCTDEC: +00 00 51.90
Instrument:
Catalog: UCAC4
Bessell (B): +*.*, Bessell (V): +*.*
Bessell (R): +14.3, Bessell (I): +*.*
CCD: ATIK-383L+
FILTERS: R
TELESCOPE: C11, 1623.0mm
PRiSMv10, Tycho
Site:
ORIGIN: Cepheid Observatory, India, Vorion Scientific, India
SITELAT: +24:55:00:00
SITELONG:+75:33:58:99
Observers:
V.K.Agnihotri, B. Kumar, S. Mahawar, K.Vora
Remark:
Sky Clear.
End

Video Link: https://www.youtube.com/watch?v=7_AREOFLgZo

C/2017 K2 (PANSTARRS)

Image:
Object: C/2017 K2 (PANSTARRS) 
DATE-OBS: 2021-04-02T22:02:41.0592
EXPTIME: 2460.00 (seconds)
SUBFRMS: 41
OBJCTRA: 18 28 03.73
OBJCTDEC: +39 34 45.90
Instrument:
Catalog: UCAC4
Bessell (B): +*.*, Bessell (V): +*.*
Bessell (R): +15.2, Bessell (I): +*.*
CCD: ATIK-383L+
FILTERS: R
TELESCOPE: C11, 1623.0mm
PRiSMv10, Tycho
Site:
ORIGIN: Cepheid Observatory, India, Vorion Scientific, India
SITELAT: +24:55:00:00
SITELONG:+75:33:58:99
Observers:
V.K.Agnihotri, B. Kumar, S. Mahawar, K.Vora
Remark:
Sky Clear.
End